Robotic surgery

ABSTRACT

A method of using a robotic guidance system for performing surgery on a spine is provided. The method includes utilizing a computerized tomographic scan image of a location on a spinal column of a patient, such that the computerized tomographic scan image is connected to a computer and visible on a monitor connected to the computer. The method also includes attaching a coupling component to the spinal column of the patient, coupling a marker to the coupling component, and imaging, with a fluoroscope, the view of the spinal column of the patient, wherein the fluoroscope image is transmitted to the computer and visible on the monitor and the at marker is clearly visible in the fluoroscope image. The method also includes positioning a cannula, with a robotic mechanism, to a first position relative to a vertebra in the spinal column of the patient, drilling a passage through the cannula into bone of the vertebra in the spinal column of the patient, inserting a guidewire through the cannula into the passage in the bone of the vertebra in the spinal column of the patient, and positioning a screw into the bone of the vertebra in the spinal column of the patient.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/965,671 filed Aug. 13, 2013, which is a continuation of U.S. patentapplication Ser. No. 13/962,269 filed Aug. 8, 2013, which is acontinuation of U.S. patent application Ser. No. 13/951,073 filed Jul.25, 2013, which is a continuation of U.S. patent application Ser. No.13/923,944 filed Jun. 21, 2013, which is a continuation of U.S. patentapplication Ser. No. 13/912,730 filed Jun. 7, 2013, which is acontinuation of U.S. patent application Ser. No. 13/888,957 filed May 7,2013, which is a continuation of U.S. patent application Ser. No.10/102,413 filed Mar. 20, 2002, which is hereby incorporated byreference in its entirety.

BACKGROUND

The present invention relates to the securing of body tissue.

Body tissue has previously been secured utilizing sutures, staples,pegs, screws, and/or other fasteners. When one or more of these knowndevices is to be utilized to secure body tissue, the device may beconcealed from view within a patient's body. Of course, this makes thesecuring of the body tissue more difficult. The manner in which a suturemay be utilized to secure body tissue is disclosed in U.S. Pat. No.6,159,234. The manner in which a staple may be utilized in associationwith body tissue is disclosed in U.S. Pat. No. 5,289,963. It haspreviously been suggested that a robotic mechanism may be utilized toassist in the performance of surgery. Various known robotic mechanismsare disclosed in U.S. Pat. Nos. 5,078,140; 5,572,999; 5,791,231;6,063,095; 6,231,565; and 6,325,808.

SUMMARY

The present invention relates to a method of securing either hard orsoft body tissue. A robotic mechanism or manual effort may be used toposition a fastener relative to the body tissue. The fastener may be asuture, staple, screw, or other known device.

The fastener may be a suture which is tensioned with a predeterminedforce by a robotic mechanism or manual effort. The robotic mechanism ormanual effort may also be used to urge a retainer toward body tissuewith a predetermined force. The suture may be gripped with the retainerwhile the suture is tensioned with a predetermined force and while theretainer is urged toward the body tissue with a predetermined force.

Alternatively, the fastener may be a staple. A robotic mechanism ormanual effort may be utilized to position the staple relative to bodytissue. The robotic mechanism or manual effort may effect a bending ofthe staple to move legs of the staple into engagement with each other.The legs of the staple may be bonded together at a location where thelegs of the staple are disposed in engagement.

Regardless of what type of fastener is utilized, a positioning apparatusmay be used to position the body tissue before and/or during securingwith a fastener. The positioning apparatus may include a long thinmember which transmits force to the body tissue. Force may betransmitted from an expanded end portion of the long thin member to thebody tissue. A second member may cooperate with the long thin member togrip the body tissue. The long thin member may be positioned relative tothe body tissue by a robotic mechanism or manual effort.

Various imaging devices may be utilized to assist in positioning afastener, such as a rivet suture or staple, relative to body tissue.Under certain circumstances at least, it may be desirable to utilize twoor more different types of imaging devices. Thus, an endoscope and amagnetic resonance imaging apparatus (MRI) may be utilized to provide animage. Alternatively, an endoscope and a fluoroscopic device may beutilized. If desired, ultrasonic imaging devices may be utilized inassociation with another imaging device, such as an endoscope ormagnetic resonance imaging device. One or more markers may be providedon fasteners to facilitate location of the fasteners in an image.

A fastener may be utilized to secure a scaffold containing viable tissuecomponents in place on body tissue. The tissue components may be stemcells, fetal cells, mesenchymal cells, and/or any desired type ofprecursor cells. It is contemplated that the scaffold with one or moredifferent types of tissue components may be positioned at any desiredlocation within a patient's body, such as within an organ, by therobotic mechanism. For example, the scaffold could be positioned in thepancreas or liver of a patient. Alternatively, the scaffold could beconnected with a bone in the patient's body. The scaffold may bepositioned relative to the body tissue by the robotic mechanism ormanual effort. One or more markers may be provided on the scaffold tofacilitate location of the scaffold in an image.

It is contemplated that the robotic mechanism may advantageously beutilized to position surgical implants other than fasteners in apatient's body. For example, the robotic mechanism may be utilized toposition a prosthesis in a patient's body. If desired, the roboticmechanism may be utilized to position a screw type fastener at aspecific location in a patient's body. The robotic mechanism may be usedto position a scaffold containing viable tissue components relative tobody tissue.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the invention will become moreapparent upon a consideration of the following description taken inconnection with the accompanying drawings wherein:

FIG. 1 is a schematic illustration depicting the manner in which arobotic mechanism and an imaging device are positioned relative to apatient's body;

FIG. 2 is a schematic illustration depicting the manner in which therobotic mechanism of FIG. 1 is utilized to move a suture anchor into apatient's body;

FIG. 3 is a schematic illustration depicting the manner in which therobotic mechanism of FIG. 1 is utilized to tension a suture with apredetermined force and urge a suture retainer toward body tissue with apredetermined force;

FIG. 4 is a schematic illustration depicting the manner in which therobotic mechanism of FIG. 1 is utilized to grip the suture with a sutureretainer while the suture is tensioned with a predetermined force andthe retainer is urged toward body tissue with a predetermined force;

FIG. 5 is a schematic illustration depicting the linear apposition ofbody tissue with sutures, anchors and retainers which were positioned bythe robotic mechanism of FIG. 1 in the same manner as illustrated inFIGS. 2-4;

FIG. 6 is a schematic illustration depicting an alternative manner inwhich body tissue may be secured by the robotic mechanism of FIG. 1using an anchor, suture and retainer;

FIG. 7 (on sheet 5 of the drawings) is a schematic illustration, similarto FIG. 4, illustrating the manner in which a pair of suture retainersare connected with a suture by the robotic mechanism of FIG. 1 to securebody tissue;

FIG. 8 is a schematic illustration, similar to FIG. 5, illustrating thelinear apposition of body tissue with a fastener which includes a sutureand plurality of suture retainers which are positioned by the roboticmechanism of FIG. 1 in the manner illustrated in FIG. 7;

FIG. 9 is a schematic illustration depicting the manner in which a longthin member of a tissue positioning assembly is moved into body tissueby the robotic mechanism of FIG. 1;

FIG. 10 is a schematic illustration of a manner in which a leading endportion of the long thin member of FIG. 9 is expanded by the roboticmechanism of FIG. 1 and transmits force from the robotic mechanism tobody tissue;

FIG. 11 is a schematic illustration depicting the manner in which ananchor is moved along the long thin member of FIG. 10 into body tissueby the robotic mechanism of FIG. 1;

FIG. 12 is a schematic illustration depicting the manner in which agripper member is moved along the long thin member of FIG. 10 by therobotic mechanism of FIG. 1 to grip body tissue and an alternativemanner in which a fastener is moved into the gripped body tissue by therobotic mechanism;

FIG. 13 is an enlarged, fragmentary sectional view further depicting themanner in which the leading end portion of the long thin member of FIG.9 is expanded by the robotic mechanism of FIG. 1;

FIG. 14 is an enlarged, fragmentary sectional view depicting anothermanner in which the leading end portion of the long thin member of FIG.9 may be expanded by the robotic mechanism of FIG. 1;

FIG. 15 is an enlarged, fragmentary sectional view depicting anothermanner in which the leading end portion of the long thin member of FIG.9 may be expanded by the robotic mechanism of FIG. 1;

FIG. 16 is a schematic illustration depicting the manner in which a longthin member of an alternative embodiment of the tissue positioningassembly is moved into body tissue by the robotic mechanism of FIG. 1;

FIG. 17 is a schematic illustration depicting how a space between upperand lower body tissues of FIG. 16 is closed by movement of the tissuepositioning assembly by the robotic mechanism of FIG. 1;

FIG. 18 is a schematic illustration depicting the manner in which afastener is moved into the body tissue of FIG. 16 by the roboticmechanism of FIG. 1 while the body tissue is positioned in the mannerillustrated in FIG. 17;

FIG. 19 is a schematic illustration depicting the manner in which aretainer may be connected with the long thin member of the tissuepositioning assembly of FIGS. 16 and 17 by the robotic mechanism of FIG.1 utilizing the apparatus of FIGS. 4 and 7;

FIG. 20 is a schematic illustration depicting an alternative manner ofutilizing the robotic mechanism of FIG. 1 to secure body tissue with asuture and retainer;

FIG. 21 is a schematic illustration depicting the manner in which astaple is positioned relative to body tissue by the robotic mechanism ofFIG. 1;

FIG. 22 is a schematic illustration depicting the manner in which thestaple of FIG. 21 is bent and end portions of the staple are bondedtogether by the robotic mechanism of FIG. 1;

FIG. 23 is a schematic illustration depicting the relationship of astaple to a portion of a stapling mechanism prior to insertion of thestaple into body tissue during operation of the robotic mechanism ofFIG. 1;

FIG. 24 is a schematic illustration, depicting the manner in which thestapling mechanism of FIG. 23 is pressed against body tissue with apredetermined force by the robotic mechanism of FIG. 1 prior toinsertion of a staple;

FIG. 25 is a schematic illustration depicting the manner in which thestaple of FIG. 24 is inserted into body tissue by operation of thestapling mechanism by the robotic mechanism of FIG. 1;

FIG. 26 is a schematic illustration depicting the manner in which thestaple of FIG. 25 is bent and legs of the staple are bonded together byoperation of the robotic mechanism of FIG. 1;

FIG. 27 is a schematic illustration depicting the relationship of viabletissue components to a scaffold or matrix;

FIG. 28 is a schematic illustration, generally similar to FIG. 27,depicting the relationship of viable tissue components to a differentscaffold or matrix;

FIG. 29 is a schematic illustration depicting the manner in which thescaffold and viable tissue components of either FIG. 27 or FIG. 28 areconnected with body tissue by staples in the manner illustrated in FIGS.24-26 by operation of the robotic mechanism of FIG. 1;

FIG. 30 is a schematic illustration depicting the manner in which thepositioning assembly of FIGS. 9 and 10 is utilized to position thescaffold of FIG. 27 or 28 relative to body tissue during operation ofthe robotic mechanism of FIG. 1;

FIG. 31 is a schematic illustration depicting the manner in which anexpandable retractor assembly is positioned by the robotic mechanism ofFIG. 1 to separate body tissue;

FIG. 32 is a schematic illustration depicting the manner in which anexpandable retractor assembly is positioned relative to a shoulder jointby the robotic mechanism of FIG. 1;

FIG. 33 is a schematic illustration depicting the manner in which anexpandable retractor assembly is positioned relative to a vertebra bythe robotic mechanism of FIG. 1;

FIG. 34 is a schematic illustration depicting the manner in which therobotic mechanism of FIG. 1 is utilized to position a threaded fastenerin body tissue;

FIG. 35 is a schematic illustration depicting the manner in which therobotic mechanism of FIG. 1 is utilized to position a prosthesis in bodytissue;

FIG. 36 is a schematic illustration, depicting the manner in which aplurality of imaging devices are used in association with the roboticmechanism of FIG. 1;

FIG. 37 is a schematic illustration depicting the manner in which afluoroscope is utilized in association with an endoscope and a roboticmechanism during the securing of body tissue in any one of the waysillustrated in FIGS. 2 through 32; and

FIG. 38 is a schematic illustration depicting the manner in which therobotic mechanism of FIG. 1 is utilized, with a magnetic resonanceimaging unit (MRI) and an endoscope, to secure body tissue in any one ofthe ways illustrated in FIGS. 2 through 32.

DETAILED DESCRIPTION

Robotic Securing of Tissue

An apparatus 30 for use in securing tissue in a patient's body isillustrated schematically in FIG. 1. Although the apparatus 30 will bedescribed herein as being used to secure tissue, it is contemplated thatthe apparatus 30 may be used for other surgical procedures if desired.

The apparatus 30 includes an operating table 32 which is disposed in asterile operating room environment. A patient 34 may be covered by aknown sterile drapery system. Alternatively, the patient 34 may becovered by a drapery system which is connected with a surgeon so as tomaintain a sterile field between the surgeon and the patient in themanner disclosed in U.S. patent application Ser. No. 09/941,185 FiledAug. 28, 2001 by Peter M. Bonutti. Of course, any desired steriledrapery system may be provided to cover the patient 34.

A robotic mechanism 38 is provided to position a tissue securing device,fastener, or other apparatus at a desired location within the patientduring performance of a surgical procedure. An imaging device 40 isoperable to provide an image of a location where the robotic mechanism38 is securing the body tissue with a fastener or performing other stepsin a surgical procedure. A programmable computer 44 is connected withthe robotic mechanism 38 through a robotic arm interface 46. Inaddition, the computer 44 is connected with the imaging device 40 and amonitor or display 48. The monitor or display 48 is visible to a surgeonoperating the apparatus 30 and provides an image of the location wherethe robotic mechanism 38 is being utilized in the performance of asurgical procedure on the patient 34.

The robotic mechanism 38 is guided by automatic controls which includethe computer 44 and robotic arm interface 46. The robotic mechanism 38may have a construction which is different than the illustratedconstruction and may include one or more adaptive arms. The roboticmechanism 38 is a reprogrammable, multifunctional manipulator designedto move through various programmed motions for the performance of asurgical procedure. The robotic mechanism 38 may have manually operablecontrols which provide for interaction between the surgeon and therobotic mechanism. The robotic mechanism 38 is utilized in the securingof a patient's body tissue. However, it is contemplated that the roboticmechanism 38 will be utilized during the performance of other surgicalsteps in addition to the securing of body tissue.

The robotic mechanism 38 may have many different constructions,including constructions similar to those disclosed in U.S. Pat. Nos.5,078,140; 5,572,999; 5,791,231; 6,063,095; 6,231,565; and/or 6,325,808.The specific robotic mechanism 38 illustrated in FIG. 1 has aconstruction and mode of operation generally similar to that disclosedin U.S. Pat. No. 5,876,325. However, it should be understood that therobotic mechanism 38 could have any desired construction. The roboticmechanism 38 may have one or more known adaptive arms.

The use of the robotic mechanism 38 and imaging device 40 enables thesize of incisions 52 and 54 in the patient's body to be minimized. Ofcourse, minimizing the size of the incisions 52 and 54 tends to reducepatient discomfort and recovery time. It contemplated that the roboticmechanism 38 and imaging device 40 will be utilized during theperformance of many different surgical procedures.

During the performances of these surgical procedures, the roboticmechanism 38 may be utilized to secure body tissue. The roboticmechanism 38 may be used to position a suture anchor 60 (FIG. 2)relative to body tissue 64 in the patient 32 during the performance ofany one of many known surgical procedures. The body tissue 64 may behard and/or soft body tissue.

Once the anchor 60 has been positioned relative to the body tissue 64,the robotic mechanism 38 is operated to tension a suture 66 connectedwith the anchor 60 with a predetermined force, in the manner indicatedschematically by an arrow 70 in FIG. 3. At the same time, the roboticmechanism 38 of FIG. 1 presses a suture retainer 72 against the bodytissue 64 with a predetermined force, indicated schematically by anarrow 74 in FIG. 3. The force 74 may be equal to, greater than, or lessthan the force 70 with which the suture 66 is tensioned.

The anchor 60, suture 66, and suture retainer 72 may be formed of anydesired material. The illustrated anchor 60, suture 66 and sutureretainer 77 are all formed of a polymeric material. The anchor 60,suture 66, and suture retainer 72 may all be formed of a biodegradablepolymeric material. However, the anchor 60, suture 66, and/or sutureretainer 72 could be formed of metal or other known materials ifdesired.

The suture 55 is a monofilament. However, the suture 66 could be formedby a plurality of filaments and could have a braided construction. Thesuture 66 could have a construction similar to the construction of arope or cable if desired.

While the suture 66 is tensioned with the predetermined force 70 andwhile the suture retainer 72 is pressed against the body tissue 64 witha force 74, the robotic mechanism 38 plastically deforms the polymericmaterial of the suture retainer 72 in the manner illustratedschematically in FIG. 4. The plastic deformation of the suture retainer72 by the robotic mechanism 38 may take place at a temperature which iseither below or in the transition temperature range for the polymericmaterial of the suture retainer 72. Thus, the suture retainer 72 may beplastically deformed by cold flowing material of the suture retainer.

Alternatively, the suture retainer 72 may be deformed by transmittingforce from the robotic mechanism 38 to the retainer after the polymericmaterial of the retainer has been heated into a transition temperaturerange of the material of the suture retainer. When the material of thesuture retainer 72 has been heated into its transition temperaturerange, the material can be readily plastically deformed with a viscousflow or movement of the material. It is believed that it may bepreferred to maintain the material of the suture 66 at a temperaturewhich is below the transition temperature range for the material of thesuture. The suture retainer 72 may be formed of the materials disclosedin U.S. Pat. No. 6,203,565 and heated in the manner disclosed in thepatent.

It is contemplated that the anchor 60, suture 66, and suture retainer 72may all be formed of biodegradable polymeric materials. However, it isbelieved that it may be desired to form the suture retainer 72 of abiodegradable material having a lower transition temperature range thanthe transition temperature range for the material of the suture 66. Thiswould facilitate operation of the robotic mechanism 38 to heat thesuture retainer 72 into its transition temperature range without heatingthe material of the suture 66 into the transition temperature of thematerial of the suture. This would minimize damage to or deformation ofthe suture 66 when the suture retainer 72 is deformed by operation ofthe robotic mechanism 38. Of course, the anchor 60, suture 66 and sutureretainer 72 could all be formed of the same biodegradable material ifdesired.

It is contemplated that, in some circumstances at least, it may bedesired to heat both the polymeric material of the suture 66 and thepolymeric material of the retainer 72 into their transition temperatureranges. If this is done, the material of the suture 66 and the retainer72 could be fused together. This would result in a blending of thematerial of the suture 66 and suture retainer 72 in the area where theyare disposed in engagement.

During operation of the robotic mechanism 38, the suture retainer 72 isbonded to the suture 66 without significant deformation of the suture.When the polymeric material of the suture retainer 72 is heated into itstransition temperature range, the material of the suture retainersoftens and loses some of its rigidity. By applying force against theheated material of the suture retainer 72, the robotic mechanism 38 canbe operated to cause the material of the suture retainer to plasticallydeform and flow around and into engagement with the suture 66.

When the material of the suture retainer 72 cools, a secure bond isformed between the material of the suture retainer and the suture 66.This bond may be formed in the manner disclosed in the aforementionedU.S. Pat. No. 6,203,565. However, it is contemplated that the materialof the suture retainer 72 could be plastically deformed and bondedwithout heating, in the manner disclosed in U.S. Pat. No. 6,010,525.

It is contemplated that the suture retainer 72 may be plasticallydeformed by operating the robotic mechanism 38 to press the forcetransmitting members 80 and 82 against opposite sides of the sutureretainer 72 in the manner indicated by arrows 84 and 86 in FIG. 4. Theforce transmitting members 80 and 82 may be pressed against oppositesides of the suture retainer 72 with sufficient force to plasticallydeform the material of the suture retainer. The resulting cold flowingof the material in the suture retainer 72 would result in the sutureretainer bonding to the suture 66.

It is contemplated that the suture retainer 72 may be heated by therobotic mechanism into the transition temperature range of the materialof the suture retainer in many different ways. For example, the sutureretainer 72 may be heated into its transition temperature range by theapplication of ultrasonic vibratory energy to the suture retainer. Ifthis is to be done, the force transmitting member 80 functions as ananvil and the force transmitting member 82 functions as a horn. Toenable the force transmitting member 82 to function as a horn, the forcetransmitting member is connected with a source 90 of ultrasonicvibratory energy by the robotic mechanism 58. One commercially availablesource of ultrasonic vibratory energy is provided by Dukane CorporationUltrasonics Division, 2900 Dukane Drive, St. Charles, Ill. Of course,there are other sources of apparatus which can be utilized to provideultrasonic vibratory energy.

When the ultrasonic vibratory energy is to be applied to the sutureretainer 72 by the robotic mechanism, the force transmitting member orhorn 82 is vibrated at a rate in excess of 20 kilohertz. Although thehorn or force transmitting member 82 may be vibrated at any desiredfrequency within a range of 20 kilohertz to 70 kilohertz, it is believedthat it may be desirable to vibrate the force transmitting member orhorn 82 at a rate which is close to or greater than 70 kilohertz. Theforce transmitting member or horn 82 is vibrated for a dwell time whichis sufficient to transmit enough ultrasonic vibratory energy to thesuture retainer 72 to heat at least a portion of the material of thesuture retainer into its transition temperature range.

The frictional heat created by the ultrasonic vibratory energytransmitted to the suture retainer 72 is sufficient to heat the materialof the suture retainer at locations adjacent to the suture 66, into thetransition temperature range of the material of the suture retainer. Asthis occurs, the softened material of the suture retainer 72 isplastically deformed by force applied against the suture retainer by theanvil or force transmitting member 80 and the horn or force transmittingmember 82. After interruption of the transmission of ultrasonicvibratory energy to the suture retainer 72, the material of the sutureretainer cools and bonds to the suture 66.

The general manner in which ultrasonic vibratory energy is applied tothe suture retainer 72 and in which the suture retainer is plasticallydeformed to grip the suture 66 is the same as disclosed in U.S. patentapplication Ser. No. 09/524,397 Filed Mar. 13, 2000 by Peter M. Bonutti,et al. and entitled Method of Using Ultrasonic Vibration to Secure BodyTissue. However, it is contemplated that the material of the sutureretainer 72 could be heated in ways other than the application ofultrasonic vibratory energy. For example, the suture retainer 72 couldbe heated by an electrical resistance heater element or by a laser.

It is contemplated that the robotic mechanism 38 may be operated tosecure the body tissue 64 in many different ways utilizing the anchor60, suture 66, and suture retainer 72. One way in which the body tissue64 may be secured is by linear apposition in the manner illustratedschematically in FIG. 5. A plurality of sutures 66 have a linearconfiguration and extend between anchors 60 disposed on one side of thebody tissue 64 and retainers 72 disposed on the opposite side of thebody tissue.

The sutures 66 are connected with openings which extend diametricallyacross the cylindrical anchors 60. However, it is contemplated that thesutures 66 could be connected with the anchors 60 in a different mannerby operation of the robotic mechanism 38. For example, it iscontemplated that the sutures 66 could be connected with the anchors 60in any one of the ways disclosed in U.S. Pat. Nos. 5,534,012; 5,713,921;5,718,717; or 5,845,645. It is also contemplated that the anchors couldhave the same construction and/or be formed of materials disclosed inany one of the aforementioned U.S. patents.

In the embodiment illustrated in FIG. 5, the body tissue 64 is formed bya pair of layers 116 and 118 of soft tissue which are held in flatabutting engagement by forces transmitted between the suture anchors 60and retainers 72 through the sutures 66. However, the suture anchors 60,sutures 66, and retainers 72 could be utilized to secure many differenttypes of body tissue. For example, the anchors 60 could be disposed in abone and the sutures 66 and retainers 72 utilized to secure soft tissue,such as a tendon or ligament with the bone. The suture anchors 60,sutures 66 and retainers 72 may be utilized for rotator cuff repairs ormeniscus repairs.

The suture anchor 60, suture 66 and retainer 72 form a fastener assemblywhich is used by surgeon controlling operation of the robotic mechanism38 to secure body tissues together or with surgical implants. Therobotic mechanism 38 may be used with many different types of fastenerassemblies during performance of surgical procedures at many differentlocations in a patient's body. The fastener assembly positioned by therobotic mechanism 38 may be a bonded rivet of the type disclosed in theaforementioned U.S. Pat. No. 6,203,565. However, it should be understoodthat the fastener assembly may have any desired construction.

The fastener assembly utilized with the robotic mechanism 38 may be usedto secure soft body tissues to each other and/or to secure soft bodytissues with hard body tissues. The fastener assembly utilized with therobotic mechanism 38 may be used to secure hard body tissues together.The robotic mechanism 38 may be used to secure a surgical implant, suchas a prosthesis, with hard and/or soft body tissue.

Anchor, Suture and Retainer Assembly

In the embodiment invention illustrated in FIGS. 1-5, the body tissue 64is secured with a fastener assembly formed by the anchor 60, suture 66and retainer 72. The fastener assembly is positioned relative to bodytissue 64 by the robotic mechanism 38, that may include one or moreadaptive arms having a known construction.

The use of the robotic mechanism 38 to position the anchor 60, suture 66and retainer 72 enables tension force in the suture 66 and force appliedagainst the body tissue by the anchor 60 and retainer 72 to beaccurately controlled. By using the imaging device 40 in associationwith the robotic mechanism 38, a surgeon can view the monitor 48 and becertain that the anchor 60, suture 66 and retainer 72 are beingpositioned in the desired manner in the patient's body. This enables thesurgeon to minimize the size of the incisions 52 and 54 and still havevisual assurance that the surgical procedure is being properly performedin the patient's body by the robotic mechanism. When the roboticmechanism 38 includes adaptive arms, input by the surgeon in response toan image on the monitor 48 is facilitated.

The robotic mechanism 38 includes a cylindrical tubular inserter member102 (FIG. 2). The inserter member 102 has a cylindrical passage 104which extends through the inserter member 102. The cylindrical passage104 has a diameter which is slightly greater than the diameter of thecylindrical anchor 60.

Although the cylindrical anchor 60 has been illustrated in FIG. 2 ashaving a blunt leading end portion, it is contemplated that thecylindrical anchor 60 could have a pointed leading end portion in themanner disclosed in U.S. Pat. No. 5,718,717. Alternatively, the anchorcould be constructed as disclosed in U.S. patent application Ser. No.09/556,458 filed May 3, 2000 by Peter M. Bonutti and entitled Method andApparatus for Securing Tissue and have a pointed leading end portion.

The anchor 60 may be formed of a material which absorbs body liquidwhile the pointed leading end portion of the anchor is formed of adifferent material that is relatively rigid and capable of piercing theimperforate body tissue 64. When the body of the anchor 60 absorbs bodyliquid, the anchor expands in all directions and forms an interlock withthe body tissue 64 in the manner disclosed in U.S. Pat. No. 5,718,717.Of course the pointed end portion of the anchor could be omitted in themanner also disclosed in the aforementioned U.S. Pat. No. 5,718,717.

When the anchor 60 is to be inserted into the body tissue by the roboticmechanism, a cylindrical pusher member 108 is pressed against thetrailing end of the anchor 60. The pusher member 108 is telescopicallymoved along the passage 104 by a suitable drive assembly in the roboticmechanism 38. When the pusher member 108 has moved the anchor to adesired position relative to the body tissues 64, the robotic mechanism38 is operated to extend a push rod 112 from the pusher member 108. Thepush rod 112 applies a force to the anchor 60 at a location offset froma central axis of the anchor. The resulting torque on the anchor 60causes the anchor to pivot relative to the body tissue 64 and changeorientation relative to the body tissue.

The manner in which the pusher member 108 is moved along the passage 104in the inserter member 102 by the robotic mechanism 38 may be the sameas is disclosed in U.S. patent application Ser. No. 09/789,621 filedFeb. 21, 2001 by Peter M. Bonutti and entitled Method of Securing BodyTissue. The manner in which the anchor 60 pivots relative to the bodytissue 64 when the push rod 112 is extended from the pusher member 108may be the same as is disclosed in U.S. Pat. No. 5,814,072. However, theanchor 60 may be pivoted relative to the body tissue 64 in a differentmanner if desired. For example, the anchor 60 could be pivoted relativeto the body tissue 64 in the manner disclosed in U.S. Pat. No.5,782,862.

In the embodiment invention illustrated in FIG. 2, the body tissue 64includes an upper or first layer or segment 116 and a lower or secondlayer or segment 118. The two layers 116 and 118 are soft body tissuesthrough which the anchor 60 is pushed by the pusher member 80. As theanchor 60 emerges from lower layer 118 of the body tissue 64, the pushrod 112 is extended to cause the anchor 60 to pivot or toggle relativeto the lower layer 118 of body tissue.

In the embodiment invention illustrated in FIG. 2, the anchor 60 ispushed through the two layers 116 and 118 of body tissue. However, it iscontemplated that the anchor 60 could be pushed through only the upperlayer 116 of body tissue. The anchor would be moved into the lower layer118 of body tissue and pivoted or toggled by extension of the push rod112 from the pusher member 108. This would position the anchor in thelower layer 118 of body tissue. It is contemplated that lower portion118 of the body tissue could be relatively thick, compared to the upperlayer 116.

If desired, the anchor 60 may not be moved through the upper layer 116of body tissue. The anchor 60 may be moved into and/or through only thelayer 118 of body tissue. Once this has been done, the suture 66 may bemoved through the layer 116 of body tissue.

It is also contemplated that the anchor could be positioned in hard bodytissue. For example, the anchor 60 could be positioned in bone in themanner disclosed in U.S. Pat. No. 6,033,430. When the anchor 60 ispositioned in bone, the suture 66 may be used to secure a tendon orligament to the bone in the manner disclosed in U.S. Pat. No. 6,152,949.Regardless of whether the anchor 60 is positioned in hard body tissue orsoft body tissue, the anchor may be formed of any one of the materialsand/or constructed in any one of the ways disclosed in theaforementioned U.S. Pat. No. 6,152,949.

Once the anchor 60 has been moved to the desired orientation relative tothe body tissue (FIG. 3), the retainer 72 is positioned relative to thesuture 66 and body tissues. The retainer 72 has a sphericalconfiguration with a diametrically extending central passage 120.However, the retainer 72 may have any desired construction, for example,any one of the constructions disclosed in U.S. Pat. No. 6,159,234.Alternatively, the retainer 72 may have any one of the constructionsdisclosed in U.S. patent application Ser. No. 09/524,397 filed Mar. 13,2000 by Peter M. Bonutti et al. and entitled Method of Using UltrasonicVibration to Secure Body Tissue.

The suture retainer 72 and suture 66 are both preferably formed of abiodegradable polymer, such as polycaperlactone. Alternatively, thesuture 66 and/or suture retainer 72 could be formed of polyethyleneoxide terephthalate or polybutylene terephthalate. It is contemplatedthat other biodegradable or bioerodible copolymers could be utilized ifdesired. The suture anchor 60 may be formed of the same material as thesuture 66 and/or retainer 72. Also, the suture 66 and/or retainer 72could be formed of an acetyl resin, such as “Delrin” (Trademark).Alternatively, the suture 66 and/or suture retainer 72 could be formedof a pora-dimethylamino-benzenediazo sodium sulfonate, such as “Dexon”(Trademark). The suture 66 may also be a monofilament or formed of aplurality of interconnected filaments.

Although it may be desired to form the anchor 60 of the same material asthe suture 66 and/or retainer 72, the anchor could be formed of adifferent material if desired. For example, the anchor 60 may be formedof body tissue, such as bone or other dense connective tissue. Theanchor 60 may be formed of many different materials containing collagen.The anchor 60 may be formed of natural or synthetic materials whichabsorb body fluid and expand when positioned in a patient's body. As theanchor expands in the patient's body, a solid interlock is obtained withadjacent tissue in the patient's body. The anchor 60 may be formed ofany of the materials disclosed in the aforementioned U.S. Pat. Nos.5,713,921 and/or 5,718,717.

Once the anchor 60 has been moved to the position illustrated in FIG. 3by operation of the robotic mechanism 38, the suture 66 is tensionedwith a predetermined force in the manner illustrated schematically bythe arrow 70. To tension the suture 66, the robotic mechanism 38(FIG. 1) includes a tensioner 122 (FIG. 3). The tensioner 122 determineswhen a predetermined tension force has been applied to the suture. Thetensioner 122 is then effective to maintain the predetermined tensionforce.

The tensioner 122 and computer 44 may be set to limit the magnitude ofthe tension applied to the suture 66 to a preselected magnitude.Alternatively, the tensioner 122 and computer 44 may have a visualreadout which enables a surgeon to determine the magnitude of thetension in the suture 66 and to maintain the tension in the suture at adesired magnitude. The image provided at the monitor 48 facilitatescontrol of the tension in the suture 66 by the surgeon. If this is done,the tensioner 122 may be set to limit the tension in the suture to adesired maximum.

The tensioner 122 may include a gripper which grips the suture 66. Adrive mechanism is operable to move to the gripper to tension the suture66. The drive mechanism includes a pezielectric cell which detects whenthe tension transmitted from the gripper to the suture 66 has reachedthe predetermined magnitude. The drive mechanism may move the gripper tomaintain the tension in the suture at the predetermined magnitude.Alternatively, the drive mechanism may respond to inputs from thesurgeon.

Of course, the tensioner 122 could have a different construction ifdesired. For example, the tensioner 122 could include a spring,deflected through a predetermined distance to maintain a predeterminedtension on the suture 66. The tensioner 122 could also have aconstruction similar to construction disclosed in U.S. patentapplication Ser. No. 09/556,458 Filed May 3, 2000 by Peter M. Bonuttiand entitled Method and Apparatus for Securing Tissue.

While the suture 66 is tensioned with a predetermined force by thetensioner 122, a retainer pusher member 126 is pressed against theretainer 72 with a predetermined force indicated schematically by anarrow 74 in FIG. 3. The retainer pusher member 126 is pressed againstthe retainer 72 by a pusher assembly 128 disposed in the roboticmechanism 38 (FIG. 1). The pusher assembly 128 includes a drive assemblywhich applies a predetermined force to the retainer pusher member 126.This force presses the retainer 72 against the upper layer 116 of bodytissue 64.

While the retainer 72 is being pressed against the body tissue 64 with apredetermined force, the suture 66 is tensioned with a predeterminedforce by the tensioner 122. The force transmitted through the suture 66presses the anchor 60 against the lower layer 118 of body tissue with apredetermined force. The force with which the anchor 60 is pressedagainst the body tissue 118 may be the same as, less than, or greaterthan the force with which the retainer is pressed against the tissue116. This results in the two layers 116 and 118 of body tissue beingclamped between the suture 60 and retainer 72 with a predeterminedforce.

The anchor 60 is pulled against a bottom surface 132 of the lower layer118 of body tissue and the retainer 72 is pressed upper against thesurface 134 of the upper layer 116 of body tissue. This results in thetwo layers 116 and 118 of body tissue being gripped between the retainer72 and anchor 60 with a predetermined compressive force. Thiscompressive force is a function of the sum of the tension force 70transmitted to suture 66 by the tensioner 122 and the force 74transmitted to the retainer pusher member 126 by the pusher assembly128. A force distribution member, such as a button, may be providedbetween the anchor 60 and surface 132 of the body tissue 118. Anotherforce distribution member may be provided between the retainer 120 andthe surface 134 of the body tissue 116.

The pusher assembly 128 may have any desired construction, including forexample, a hydraulically actuated piston and cylinder type motor inwhich the fluid pressure determines the magnitude of the force 74.Alternatively, an electric motor could be associated with a screw typedrive and a force measurement device to apply the force 74 to theretainer pusher member 126. The force measurement device may be apiezoelectric cell or a spring assembly to control energization of theelectric motor.

While anchor 60 and retainer 72 are being pressed against theirrespective body tissues, the robotic mechanism 38 is effective toplastically deform the retainer 72 to grip the suture 66. A retainerdeformation assembly 144 (FIG. 4) in the robotic mechanism 38 is movedalong the retainer pusher member 126 and suture 66 into engagement withthe upper layer 116 of body tissue. A drive assembly 148 in the roboticmechanism 38 is effective to press the retainer deformation assembly 144against the upper layer 116 of body tissue with a predetermined force.The force with which the retainer deformation assembly 144 is pressedagainst the upper layer 116 of body tissue may be of the same magnitudeor less than the force 74 with which the retainer 72 is pressed againstthe upper layer 116 of body tissue by the robotic mechanism 38.

The retainer deformation assembly 144 includes a tubular cylindricalinner member 152 having a central cylindrical passage 154 in which theretainer pusher member 126 is telescopically received. A cylindricalouter member 156 extends around the cylindrical inner member 152 and isdisposed in a coaxial relationship with the inner member 152 andretainer pusher member 126.

The force transmitting members 80 and 82 are carried by the inner member152. When the inner member 152 is pressed against the upper layer 116body tissue, the force transmitting members 80 and 82 are aligned withthe suture retainer 72. At this time, the force transmitting members 80and 82 are disposed below (as viewed in FIG. 4) a lower end of thepusher member 126 and are disposed radially outward from the sphericalretainer 72.

When the retainer 72 is to be plastically deformed to grip the suture66, the outer member 156 is moved downward (as viewed in FIG. 4) towardthe upper layer 116 of body tissue by a drive assembly 160 disposed inthe robotic mechanism 38. The drive assembly 160 presses the lower (asviewed FIG. 4) end of the outer member 156 against the forcetransmitting member 84 and 86 with a predetermined force, indicatedschematically at 162 in FIG. 4. This force cams the force transmittingmembers 80 and 82 radially inward against the suture retainer 72.

The camming force 162 transmitted from the outer member 156 to the forcetransmitting members 80 and 82 causes the force transmitting members tomove inward toward the suture retainer 72, as indicated by arrows 84 and86. The force indicated by the arrows 84 and 86 causes the passage 120(FIG. 3) to collapse and the material of the suture retainer 72 to moveinto engagement with and grip the suture 66. The manner in which thematerial of the retainer 72 is plastically deformed by the forcetransmitting members 80 and 82 may be the same as is disclosed in U.S.Pat. No. 6,159,234.

In order to facilitate deformation of the retainer 72, the material ofthe suture retainer may be heated. Heating of the material of theretainer 72 results in the material becoming soft and malleable underthe influence of forces 84 and 86 applied by the force transmittingmembers 80 and 82. Ultrasonic vibratory energy is transmitted to theforce transmitting member 82 from a source or generator 90 of ultrasonicvibratory energy. The force transmitting member 82 functions as a hornand applies the ultrasonic vibratory energy to the retainer 72. Theforce transmitting member 80 acts as an anvil which presses against theopposite side of the retainer 72.

As ultrasonic vibratory energy is transmitted to the retainer 72 and thetemperature of the retainer increases, the material of the retainer isheated into its transition temperature range and softens. As thematerial of the retainer 72 softens, the forces 84 and 86 appliedagainst the retainer by the force transmitting members 80 and 82 causethe material of the suture retainer to flow or ooze around and engagethe suture 66.

The softened material of the retainer 72 engages the suture and bonds tothe suture without significant deformation of the suture. Materials ofthe suture 66 and retainer 70 are chemically compatible so that amolecular bond can be established between the retainer and the suture.Like materials, that is materials having chemical properties which arethe same or very similar, usually bond together. However, dissimilarmaterials may bond if their melt temperatures are reasonably close andthey are of like molecular structure. Generally speaking, amorphouspolymers are readily bonded to each other.

While it is preferable to heat the material of the retainer 72 by theapplication of energy, such as ultrasonic vibratory energy, othersources of energy could be used. For example, the retainer 72 could beheated by a laser or resistance wire. Regardless of whether or not thematerial of the retainer 72 is heated, the suture 66 is tensioned withthe predetermined force 70. At the same time, the retainer 72 is urgedtoward the body tissue 64 of the predetermined force 74 when theretainer 72 is plastically deformed to grip the suture 66.

The anchor 60 could be formed out of body tissue in the manner disclosedin the aforementioned U.S. Pat. No. 5,713,921. The body tissue may bebone. If the anchor is formed of bone, the anchor may be formed witheither the configuration illustrated in FIGS. 2-4 or may have aconfiguration similar to that disclosed in U.S. patent application Ser.No. 09/556,458 Filed May 3, 2000, by Peter M. Bonutti and entitledMethod And Apparatus For Securing Tissue. Alternatively, the anchorcould have any one of the constructions disclosed in U.S. Pat. Nos.5,527,343; 5,534,012 and 5,718,717.

The inserter member 102 could have a construction different from theconstruction illustrated in FIG. 2. For example, the inserter member 102could have a construction similar to any one of the constructionsdisclosed in U.S. Pat. No. 6,033,430.

Linear Apposition

The robotic mechanism 38 may be operated to place the layers 116 and 118of body tissue in a side-by-side relationship, in the manner illustratedschematically in FIG. 5. When the layers of body tissue have been placedin the side-by-side relationship by the robotic mechanism 38, the pushermember 108 and inserter member 102 are utilized to move each of theanchors 60 in turn through the two layers 116 and 118 of body tissue inthe manner previously discussed in connection with FIGS. 2-4 herein.While each of the sutures 66 in turn is tensioned, the retainer 72 isplastically deformed to securely grip the suture. Although each of theanchors 60, sutures 66 and retainers 72 of FIG. 5 was positionedrelative to the body tissue 64 by the robotic mechanism 38 in turn, therobotic mechanism could be constructed so as to position a plurality ofthe anchor 60, suture 66 and retainers 72 relative to the body tissue 64at one time.

Regardless of how the anchor 60, suture 66 and retainers 72 arepositioned relative to the body tissue 64, each of the sutures 66 istensioned so that it extends in a straight line between an anchor 60 andretainer 72 in the manner illustrated in FIG. 5. The anchors 60, sutures66 and retainers 72 are spaced a desired distance apart along the edgesof the body tissue 64 to secure the body tissue in linear apposition, asillustrated in FIG. 5. It is also possible that the layers 116 and 118could be interconnected in a different manner if desired. For example,the robotic mechanism 38 could be operated to connect the layers 116 and188 of body tissue in the manner disclosed in U.S. Pat. No. 5,549,631.

Under certain circumstances, body tissues are preferably joined inend-to-end relationship rather than the side-by-side relationshipillustrated schematically in FIG. 5. For example, a break 172 may beformed between portions 174 and 176 of body tissue 64 (FIG. 6) byoperation of the robotic mechanism 38. When the portions 174 and 176 ofthe body tissue are to be secure in this orientation, the suture anchorinserter member 102 and pusher number 108 (FIG. 2) are skewed at anacute angle relative to an upper (as viewed in FIG. 6) side surface 178and to a lower side surface 180 of the portions 174 and 176 of the bodytissue 64. Of course, the retainer deformation assembly 144 would alsobe skewed at a similar angle relative to the side surfaces 178 and 180of the body tissue 64. This would allow the sutures 66 to be tensionedacross the joint 172 between the two portions 174 and 176 of the bodytissue 64. This would be particularly advantageous to provide thesutures 66 with the orientation illustrated in FIG. 6 when the portions174 and 176 of body tissue to be interconnected are formed of bone.

A plurality of anchors 60, sutures 66 and retainer 72 may be providedacross the break 172 between the portions 174 and 176 of a bone to beinterconnected in the manner disclosed U.S. Pat. No. 6,117,160. Itshould be understood that the suture 66 could be utilized to connectsoft body tissue with the portions 174 and 176 of bone in much the samemanner as is disclosed in U.S. Pat. No. 6,117,160 and/or U.S. Pat. No.6,152,949. The anchor 60, suture 66, and retainer 72 may be utilized tointerconnect bone fragments in a manner similar to that disclosed inU.S. Pat. No. 6,117,160.

Plural Retainers

In the embodiments of the invention illustrated in FIGS. 2-6, an anchor66 and retainer 72 have been connected with a suture. However, it iscontemplated that a plurality of retainers 72 could be connected with asingle suture. This could result in the suture 66 being tensionedbetween a pair of retainers 72 in the manner illustrated in FIG. 7 byoperation of the robotic mechanism 38.

The two layers 116 and 118 of body tissue 64 (FIG. 7) are moved into aside-by-side relationship by operation of the robotic mechanism 38. Therobotic mechanism 38 then utilizes a needle or other suture passer tomove the suture 66 through the two layers of body tissue. The suture 66may be moved through the body tissue 64 in the manner disclosed in U.S.patent application Ser. No. 10/005,652 filed Dec. 3, 2001, by Peter M.Bonutti for Magnetic Suturing System and Method. Of course, other knownmethods could be utilized in association with the robotic mechanism 38to move the suture through the body tissue 64.

The retainers 72, (FIG. 7) are moved into engagement with the suture 66.The suture 66 is tensioned between upper and lower tensioners 122. Whilethe suture 66 is tensioned by a pair of tensioners 122 (FIG. 7), a pairof retainer pusher members 126 press the retainers 72 against the upperand lower layers 116 and 118 of body tissue with predetermined forces,indicated by arrows 74 in FIG. 7. This results in the layers 116 and 118of body tissue being firmly gripped between the upper and lowerretainers 72 with a predetermined force.

While the suture 66 is being tensioned with a predetermined force andwhile the retainers 72 are being pressed against the layers 116 and 118with a predetermined force, the pair of retainer deformation assemblies144 are pressed against opposite sides of the body tissue 64 by driveassemblies 148. The retainer deformation assemblies 144 are pressedagainst the body tissue with a predetermined force which may be the sameas the force with which the retainers 72 are pressed against the twolayers 116 and 118 of body tissue.

The force transmitting members 80 and 82 are moved radially inwardagainst spherical outer side surfaces of the upper and lower retainers72. To press the force transmitting members 80 and 82 against theretainers 72 with a predetermined force, an upper tubular cylindricalouter member 156 is moved downward toward the upper layer 116 of bodytissue 64 by a drive assembly 160. At the same time, a lower tubularcylindrical outer member 156 is moved upward toward the lower layer 118of body tissue by a drive assembly 160, causing the upper and lowerforce transmitting members 80 and 82 to be jammed radially inward towardthe retainers 72 to plastically deform the retainers and securely gripthe suture 66.

As it was previously described in conjunction with the embodiment of theinvention illustrated in FIG. 4 ultrasonic vibratory energy can betransmitted from a generator 90 connected with the upper forcetransmitting member 82 and from a generator 90 connected with the lowerforce transmitting member 82 to effect a heating of the material of thesuture retainers 72. Of course, heat energy could be transmitted to theretainers 72 in a different manner if desired. Also, the retainers 72could be plastically deformed without being heated.

Once the two retainers 72 have gripped the suture 66, the roboticmechanism 38 is operated to withdraw the retainer deformation assemblies144 and pusher members 126, suitable cutters are then utilized to trimthe suture 66. This may be accomplished in the manner disclosed in theaforementioned U.S. patent application Ser. No. 09/556,458 filed May 3,2000.

A plurality of retainer and suture assemblies may be utilized to effectthe linear apposition of body tissue in the manner illustrated in FIG.8. The sutures 66 are tensioned and connected in a straight linerelationship between retainers 72. This enables the sutures 66 andretainers 72 to hold the two layers 116 and 118 of body tissue in aside-by-side relationship with each other.

The linear apposition of the layers 116 and 118 of body tissue in themanner illustrated in FIGS. 5 and 8 and the linear interconnection ofportions 174 and 176 of body tissue 64 in FIG. 6 result in a spot weldeffect between separate pieces of body tissue at the locations where thesutures 66 extend through the of body tissue. The straight lineconnection provided by the suture 66 extending between either an anchor60 and retainer 72 or two retainers 72, holds the portions 116 and 118of body tissue against movement relative to each other when thepatient's body moves. If the portions of body tissue were interconnectedwith a looped suture, the pieces of body tissue could shift relative toeach other when the patient moves.

Although only a single suture 66 has been illustrated in FIG. 6, itshould be understood that a plurality of sutures are disposed in alinear array along the joint 172. Although the suture 66 has beenillustrated in FIG. 6 as being connected between an anchor 60 andretainer 72, the suture 66 could be connected a plurality of retainers72 in the same manner as illustrated in FIG. 8.

In FIGS. 5 through 8, the anchors 60, sutures 66 and retainers 72 arepreferably all formed of the same biodegradable polymeric material.However, it is contemplated that the anchors 60, sutures 66, and/orretainers 72 could be formed of different materials if desired. Forexample, the anchors 60 and/or retainers 72 could be formed of collagen.Alternatively, the anchors 60 and/or retainers 72 could be formed ofbody tissue, such as bone, in the manner disclosed in U.S. Pat. No.5,713,921 and/or U.S. patent application Ser. No. 09/556,458 Filed May3, 2000 and entitled Method and Apparatus For Securing Tissue.

Although it is preferred to utilize the robotic mechanism 38 to positionthe anchors 60, sutures 66 and retainers 72, they could be manuallypositioned in the body tissue if desired. For example, the anchors couldbe positioned in either hard or soft body tissue in the manner disclosedin U.S. Pat. No. 5,527,343 or 6,033,430. However, it is preferred toutilized the robotic mechanism 38 to position the anchors 60, sutures 66and retainers 72 in the manner previously described in order tofacilitate accurate positioning and tensioning of the sutures withminimally invasive surgery.

Tissue Positioning Assembly

A tissue positioning assembly 200 (FIGS. 9-15) forms part of the roboticmechanism 38 (FIG. 1), but may be manually operated separately. Althoughthe tissue positioning assembly 200 is advantageously utilized inconjunction with the robotic mechanism 38, it may be utilized withoutthe robotic mechanism 38. Thus, the tissue positioning assembly mayadvantageously be utilized when body tissue 64 is to be manually securedutilizing prior art methods.

The tissue positioning assembly 200 includes a long thin member 202connected with and moved by the robotic mechanism 38. The long thinmember 202 has a leading end portion 204 which is utilized to pierce thelayers 116 and 118 of body tissue 64. The leading end portion 204 of thelong thin member 202 is pointed to facilitate piercing imperforatesurface areas on the layers 116 and 118 of body tissue 64.

The long thin member 202 is illustrated in FIG. 9 as being moved throughthe layers 116 and 118 of body tissue while there is a space 208 betweenthe layers of body tissue. Although it is believed that the long thinmember 202 may advantageously pierce imperforate surfaces on the layers116 and 118 of body tissue 64 while they are spaced apart in the mannerillustrated schematically in FIG. 9, the long thin member 202 may beutilized to pierce the layers 116 and 118 of body tissue while they aredisposed in engagement with each other. The long thin member 202 piercesthe layers 116 and 118 of body tissue under the influence of forcetransmitted to the long thin member from the robotic mechanism 38, butmay be moved manually.

The tissue positioning assembly 200 may be utilized in association withtwo or more pieces of bone. Thus, the long thin member 202 could bemoved across a fracture or break in a bone or could extend through amain portion of a bone and a bone fragment during interconnection of theseparate portions of the bone in a manner similar to that disclosed inU.S. Pat. No. 6,045,551. Similarly, the tissue positioning assembly 200may be used with both hard and soft body tissue, as disclosed in U.S.Pat. No. 5,527,343 and/or U.S. patent application Ser. No. 09/789,621filed Feb. 21, 2001, by Peter M. Bonutti and entitled Method of SecuringBody Tissue.

The leading end portion 204 of the long thin member 202 is expandablefrom the contracted condition of FIG. 9 to the expanded condition ofFIG. 10 after the long thin member 202 has been inserted through the twolayers 116 and 118 of body tissue and while the space 208 is presentbetween the two layers of body tissue. Once the leading end portion 204of the long thin member 202 has been expanded, a force indicatedschematically in 212 in FIG. 10, is applied to the long thin member 202.The axial force applied to the long thin member 202 pulls the long thinmember upward (as viewed in FIGS. 9 and 10).

As the long thin member 202 is pulled upward, the expanded leading endportion 204 (FIG. 10) moves into abutting engagement with a surface onthe lower layer 118 of body tissue 64. The force 212 is transmitted fromthe expanded leading end portion 204 to the lower (as viewed in FIG. 10)surface 132 of the layer 118 of body tissue. The force 212 istransmitted to the long thin member 202 from the robotic mechanism 38.However, the force 212 could be manually applied to the long thin memberif desired.

The force on the lower layer 118 of body tissue pulls the lower layer ofbody tissue upward toward the upper layer 116 of body tissue,eliminating space 208 (FIG. 9) between the layers 116 and 118 of bodytissue. Therefore, an upper surface of the layer 118 of body tissuemoves into engagement with a lower surface of the layer 116 of bodytissue.

The tissue positioning assembly 200 may be used to move the layers 116and 118 of body tissue together to a desired position in a patient'sbody. Thus, after the upper and lower layers 116 and 118 of body tissue64 have been moved into engagement (FIG. 10), they may be movedsidewardly in the patient's body. This may be accomplished by applying,to the long thin member 202, a force which extends transverse to centralaxis of the long thin member. This transverse force moves the long thinmember 202 and the layers 116 and 118 of body tissue to either the leftor the right as viewed in FIG. 10. The transverse force can betransmitted from the robotic mechanism or manually applied.

If desired, a cannulated anchor 216 (FIG. 11) may be moved along thelong thin member 202 into the body tissue 64. The anchor 216 is movedunder the influence of force applied against the trailing end of theanchor 216 by a tubular cylindrical pusher member 220 (FIG. 11). Thepusher member 220 has a cylindrical central passage 222 through whichthe long thin member 202 and suture 66 extend. The suture 66 isconnected to the cannulated anchor 216.

The pusher member 220 applies an axial force to the cannulated anchor216. This force slides the anchor 216 along the long thin member 200 tomove the anchor 216 through the upper (as viewed in FIG. 11) layer 116of body tissue into the lower layer 118 of body tissue.

As the anchor 216 moves through the lower layer 118 of body tissue to aposition adjacent to the expanded leading end portion 204, the leadingend portion 204 is returned to the contracted condition of FIG. 9. Theanchor 216 is then pushed downward (as viewed in FIG. 11) through thelower layer 118 of body tissue, becoming disengaged from the long thinmember 202. Thus, the cannulated anchor 216 is pushed or slid off of thecontracted leading end portion 204.

The long thin member 202 is then withdrawn from the body tissue 64 and,contemporaneously with withdrawal of the long thin member 202, theanchor 216 is pivoted or toggled to the orientation of the anchor 60 inFIG. 3. Once this has been accomplished, tensioning of the suture 66 iseffective to press the anchor 216 firmly against the surface 132 of thelower (as viewed in FIG. 11) layer 118 of body tissue.

A retainer 72 is then pressed against the upper layer 116 of body tissueby a retainer pusher member, corresponding to the retainer pusher member126 of FIG. 3. While the retainer is pressed against the body tissuewith a predetermined force and the suture 66 is tensioned with apredetermined force, the suture retainer is deformed to grip the suture66 in the same manner as previously described in conjunction with FIG.4.

The cannulated anchor 216 has been illustrated as having a fustroconical leading end 226 which is connected with a cylindrical body 228.The conical configuration of the leading end 226 of the anchorfacilitates movement of the anchor through the body tissue 64 under theinfluence of force applied against the trailing end of the anchor by thepusher member 220. However, the anchor 216 could have a differentconfiguration, for example, a configuration corresponding to theconfiguration of the anchors FIGS. 2 and 3 herein.

The long thin member 202 is moved into the body tissue 64, the leadingend portion 204 expanded, and the long thin member pulled upward, asviewed in FIG. 10, under the control of the robotic mechanism 38.However, these steps could all be performed apart from the roboticmechanism 38 if desired. For example, these steps could be performed bya mechanism which is separate from the robotic mechanism 38.Alternatively, these steps could be performed manually.

In the embodiment illustrated in FIG. 11 the anchor 216 is moved alongthe long thin member 202 with a central axis of the anchor coincidentwith a central axis of the long thin member. In the embodimentillustrated in FIG. 12, the anchor 60 is moved along the long thinmember with the anchor offset to one side of the long thin member. Asthe anchor 60 transmits a downwardly directed (as viewed in FIG. 12)force from the pusher member 108 to the body tissue 64, the long thinmember 202 transmits an upwardly directed force 212 to the body tissue.As was previously mentioned, the long thin member 202 may also apply asideward force, that is, a force transverse to the central axis of thelong thin member, to the body tissue 64. The results in the body tissue64 being maintained in a desired position during movement of the anchor60 through the layer 116 of body tissue into the layer 118 of bodytissue.

The anchor 60 may be pivoted or toggled in the layer of body tissue 118in response to axially downward movement of the push rod 112 (FIG. 12).As the push rod 112 is pressed downward against the anchor 60 by therobotic mechanism 38, a torque is applied to the anchor 60. This torquecauses the anchor 60 to pivot and deflect body tissue 118 in the mannerdisclosed in U.S. Pat. No. 6,033,430. Once the anchor 60 has pivoted tothe orientation shown in FIG. 3 with the anchor enclosed by the bodytissue 118, tension forces in the suture 66 are transmitted through theanchor 60 to the body tissue 118. Downward forces applied to the bodytissue 64 by the anchor 60 during pivoting of the anchor are offset byupward force transmitted through the thin elongated member 202 to thebody tissue.

After the anchor 60 has been pivoted to the desired orientation in thebody tissue 118, the long thin member 202 is withdrawn from the twolayers 116 and 118 of body tissue 64. Before this can be done, theleading end portion 204 of the long thin member 202 is operated from theexpanded condition of FIG. 12 to the contracted condition of FIG. 9. Thelong thin member 202 can then be pulled from the body tissue 64 byeither operation of the robotic mechanism 38 or the application ofmanual force to the long thin member.

Although the anchor 60 has been described above as moving only part waythrough the lower layer 118 of body tissue, the anchor 60 could be movedcompletely through the lower layer 118 of body tissue and into theorientation shown in FIG. 3. Tensioning the suture 66 would then resultin force being transmitted from the anchor 60 to the lower (as viewed inFIG. 12) surface 132 of the layer 118 of body tissue.

It is contemplated that it may be desired to grip the two layers 116 and118 of body tissue with a clamping action. When this is to be done, atubular cylindrical gripper member 232 is pressed against the surface134 on the upper (as viewed in FIG. 12) layer 116 of body tissue 64.This clamps the two layers 116 and 118 of body tissue between thegripper member 232 and the expanded leading end portion 204 of the longthin member 202. Thus, the long thin member 202 is pulled upward (asviewed in FIG. 12) with the force 212 to press the expanded leading endportion 204 of the long thin member against the lower surface 132 of thelayer 118 of body tissue. At the same time, the gripper member 232 ispressed against the upper surface of the layer 116 of body tissue with aforce indicated at 234 in FIG. 12.

The anchor 60 is moved along the long thin member 202 into the bodytissue 64 at a location offset to one side of and disposed adjacent tothe long thin member 202. The tissue positioning assembly 200 (FIG. 12)is effective to grip the body tissue 64 between the gripper member 232and the expanded end portion 204 of the long thin member 202. The tissuepositioning assembly 200 is effective to hold the gripped body tissue 64in any desired position in the patient's body.

The gripped body tissue 64 can be moved to any desired position in thepatient's body by moving the long thin member 202 and gripper member232. Thus, the long thin member 202 and gripper member 232 can be movedupward, downward, and/or sideward while gripping the body tissue 64. Thelong thin member 202 and gripper member 232 can be moved manually or bythe robotic mechanism 38 to move the body tissue 64 to a desiredlocation in a patient's body.

While the anchor 60 is pushed through the two layers 116 and 118 of bodytissue by the pusher member 108 as previously described in conjunctionwith FIG. 2 herein, the body tissue is gripped by the long thin member202 and gripper member 232. Since the body tissue 64 is securely held,the body tissue does not move under the influence of force transmittedfrom the pusher member 108 through the anchor 60 to the body tissue asthe anchor moves through the body tissue. Thus, when the anchor 60 movesinto the body tissue, the anchor applies a force which urges the bodytissue to move downward (as viewed in FIG. 12). The upward (as viewed inFIG. 12) force 212 transmitted to the leading end portion 204 of thelong thin member 202 through the body tissue 64 holds the body tissue ina desired position as the anchor 60 moves into the body tissue. Inaddition, the long thin member 202 is effective to hold the body tissueagainst sideways movement during insertion of the anchor 60 into thebody tissue.

Once the anchor 60 has been moved to a desired position relative to thebody tissue 64, the long thin member 202 and gripper member 232 (FIG.12) hold the gripped body tissue in a desired position against theinfluence of force transmitted through the suture 66. This enables thesuture 66 to be tensioned without moving the body tissue 64. After thesuture 66 has been connected in any desired manner, the long thin member202 and gripper member 232 are disengaged from the body tissue 64.

It is preferred to have the tissue positioning assembly 200, theinserter member 102, and the pusher member 108 be part of the roboticmechanism 38. The force transmitted from the robotic mechanism to theinserter member 102 and pusher member 108 enables the anchor 60 to bepushed into the body tissue 64 with a desired force. However, it shouldbe understood that the tissue positioning assembly 200, the insertermember 102, and the pusher member 108 could be separate from the roboticmechanism 38 and could be manually operated.

The tissue positioning assembly 200 may also be utilized to indicate thedepth to which the anchor 60 must be moved into the body tissue 64 bythe pusher member 108. The leading ending portion 204 of the long thinmember 202 (FIG. 12) is disposed at a known depth relative to the bodytissue. By moving the anchor 60 to a depth which slightly exceeds thedepth of the leading end portion 204 of the long thin member 202, theanchor 60 is pushed to a known depth relative to the body tissue.

An encoder connected with a drive assembly in the robotic mechanism 38may be utilized to indicate the depth to which the long thin member 202is moved into the patient's body. By comparing the depth of the thinmember 202 in the patient's body with the depth to which the grippermember 232 is moved into the patient's body, the thickness of the bodytissue 64 can be determined. This enables the robotic mechanism 38 tomove the inserter member 102 to a position in engagement with the uppersurface 134 of the layer 116 of body tissue 64. It also enables therobotic mechanism 38 to be operated to move the pusher member 108through a distance sufficient to push the anchor 60 through both theupper layer 116 of body tissue and the lower layer 118 of body tissue tothe position corresponding to the position illustrated in FIG. 3. Ifdesired, the anchor 60 may be moved to a position in the lower layer 118of body tissue.

When the tissue positioning assembly 200, inserter member 102, andpusher member 108 are to be manually moved relative to the body tissue64, indicia to indicate the depth of movement of the various members maybe provided on the outside of various members. The indicia may benumerical indicia indicating the depth of insertion of a member into thebody tissue. Alternatively, the indicia may be colored bands or othermarkings. If the indica is to be colored bands, the indicia may besimilar to the indicia disclosed in U.S. Pat. No. 6,056,772.

Once the anchor 60 (FIG. 12) has been moved through layers 116 and 118of the body tissue 64 while the tissue positioning assembly 200 gripsthe body tissue and holds it into a desired position, the suture 66 istensioned with a predetermined force and a retainer is deformed to gripthe suture. The retainer may have the same construction as the retainer72 of FIG. 4. Alternatively, the suture retainer may have any one of theconstructions disclosed in U.S. Pat. No. 6,159,234.

A retainer deformation assembly having the same construction as theretainer deformation assembly 144 (FIG. 4) may be utilized to deform theretainer to grip the suture 66 of FIG. 12. This results in the bodytissue 64 being clamped or gripped between the anchor 60 and a retainer72 which grips the suture 66. This holding or gripping action would bethe same as was previously described in conjunction with FIGS. 2-4herein. Of course, other known retainer deformation assemblies could beutilized if desired, as noted above.

Once the body tissue has been gripped between the anchor 60 and theretainer 72 and the retainer secured to the suture 66, the tissuepositioning assembly 200 is disengaged from the body tissue as notedabove.

It is contemplated that the leading end portion 204 of the long thinmember 202 may include a resilient panel 240 (FIG. 13). The panel 240 ismoved from a contracted condition, shown in dashed lines in FIG. 13, tothe expanded condition of FIGS. 10, 11, 12 and 13 with fluid pressure.When the leading end portion 204 of the long thin member 202 is in thecontracted condition of FIG. 9, the resilient panel collapses radiallyinward from the expanded condition to the contracted condition under theinfluence of its own natural resilience. When the panel 240 is in thecontracted condition, a cylindrical outer side surface of the resilientpanel 240 is aligned with a cylindrical outer side surface 244 of thelong thin member 202. At this time, the resilient panel 240 is disposedin an annular recess 246 formed in the leading end portion 204 of thelong thin member 202.

When the leading end portion 204 of the long thin member 202 is to beexpanded, fluid under pressure is conducted through a passage 250 in thelong thin member to the annular recess 246 in the leading end portion ofthe long thin member. This fluid pressure is applied against an innerside surface of the resilient panel 240. The fluid pressure forces theresilient panel 240 to expand outward to the annular configurationillustrated in solid lines in FIG. 13. The fluid pressure appliedagainst the inner side of the panel 240 could be either a liquid or gaspressure. Thus, the robotic mechanism 38 is operable force either a gasor a liquid through the passage 250.

When relatively large forces are to be transmitted from the leading endportion 204 of the long thin member 202 to the body tissue 64, it may bepreferred to utilize a liquid to effect radial expansion of the panel240. When somewhat smaller forces are to be transmitted from the longthin member 202 to the body tissue 64, the resilient panel 240 may beexpanded under the influence of gas pressure.

The long thin member 202 has a pointed end 254 which is utilized topierce imperforate areas on upper and lower surfaces of the upper layer116 of body tissue and on upper and lower surfaces of the lower layer118 of body tissue. The pointed end 254 of the long thin member 202 iscoaxial with the longitudinal central axis of the long thin member andhas a conical configuration. The pointed end 254 of the long thin member202 is immediately ahead of and coaxial with the resilient panel 240.

The resilient panel on the leading end portion 204 of the long thinmember may be formed of any desired resilient material which can beexpanded under the influence of fluid pressure. It is contemplated thatthe resilient panel 240 will be formed of a polymeric material. Theremainder of the long thin member 202 may be formed of either metal or apolymeric material.

An alternative embodiment of the long thin member 202 is illustrated inFIG. 14. In this embodiment, the resilient panel 240 is formed as aportion of a circle. This results in the resilient panel bulging outwardfrom one side of the long thin member 202 when fluid pressure isconnected through the passage 250 to a recess 246 in the leading endportion 204 of the long thin member 202. The recess 246 has aconfiguration corresponding to a portion of a cylinder.

When the leading end portion 204 is in the contracted condition, theresilient panel 240 is disposed in the position indicated in dash linesin FIG. 14. At this time, the resilient panel 240 is disposed within therecess 246. When fluid pressure is conducted through the passage 250 tothe recess 246, the resilient panel 240 is expanded radially outwardfrom the long thin member 202 to the position shown in solid lines inFIG. 14. Other than the configuration of the resilient panel 240, thelong thin member 202 of FIG. 14 has the same construction as the longthin member 202 of FIG. 13.

In the embodiment of the long thin member 202 illustrated in FIG. 15, aplurality of longitudinally extending elements 260 are disposed in acylindrical array on the leading end portion 204 of the long thin member202. The longitudinally extending elements 260 are spaced apart fromeach other and have longitudinal central axes extending parallel to alongitudinal central axis of the long thin member 202. Thelongitudinally extending elements 260 are pivotally connected at 264 toa cylindrical main portion 266 of the long thin member 202. A pointedend 254 of the long thin member 202 is connected with a cylindricalactuator rod 268 which extends through the main portion 266 of the longthin member to the pointed end 254. By pulling upwards (as viewed inFIG. 15) on the long thin member, the longitudinally extending elements260 are bent at central pivots 272. The long thin elements are connectedwith the pointed end 254 at pivots 274.

Pulling upward, in the manner indicated by an arrow 276 in FIG. 15transmits force through the actuator rod 268 to the pointed end 254 ofthe long thin member 202. This moves the pointed end 254 of the longthin member toward the main portion 266 of the long thin member. As thisoccurs, the longitudinally extending elements 260 are bent at the pivotconnections 264, 272 and 274 and move radially outward away from alongitudinal central axis of the long thin member 202. This results inthe longitudinally extending elements performing an annular projectionwhich extends around the long thin member 202. This annular projectionis pressed against body tissue by pulling upward on the main portion 266of the long thin member 202.

The longitudinally extending elements 260 of FIG. 15 are formedseparately from the main portion 266 of the long thin member 202.However, the longitudinally extending elements 260 may be integrallyformed as one piece with the main portion 266 of the long thin member202. If this was done, the longitudinally extending elements 260 wouldbe resiliently deflected radially outward from the contracted conditionto the expanded condition. This may be accomplished in the mannerdisclosed in U.S. Pat. No. 5,667,520.

Although the long thin member 202 has been illustrated in FIGS. 9-12 inassociation with layers 116 and 118 of soft body tissue 64, it iscontemplated that the long thin member 202 could be utilized with hardbody tissue if desired. For example, the pointed leading end 254 of thelong thin member 202 could be forced through a hard cortical outer layerof a portion of a bone in a patient's body. Alternatively, the leadingend portion 204 could be moved into the bone through a drilled passage.

The leading end portion 204 of the long thin member 202 would then beexpanded in the bone, under the influence of fluid pressure and/or forcetransmitted through the long thin member. Expansion of the leading endportion 204 of the long thin member 202 would deflect the relativelysoft consellous bone enclosed by the hard cortical outer layer of bone.This would result in the long thin member being secured with the bone.

After the leading end portion 204 of the long thin member 202 has beenexpanded in a bone, the gripper member 232 (FIG. 12) may be movedaxially along the long thin member 202 to press soft body tissue, suchas the layer 116 of soft body tissue, against the bone. This wouldresult in the soft body tissue and the hard cortical outer layer of thebone being gripped between the leading end portion 204 of the long thinmember 202 and the gripper member 232 in the same manner as in which thelayers 116 and 118 of soft body tissue are clamped between the grippermember 232 and the expanded leading end portion 204 of the long thinmember 202 in FIG. 12.

In the embodiment illustrated in FIGS. 9-12, the leading end portion 204of the long thin member 202 is moved through the body tissue and iseffective to apply force against an outer surface 132 of the lower layer118 of body tissue. However, it is contemplated that the long thinmember may be moved only part way through the layer 118 of body tissue.This would result in the leading end portion 204 of the long thin memberbeing operated from the contracted condition of FIG. 9 to the expandedcondition of FIGS. 11 and 12 while the leading end portion of the longthin member is disposed in the layer 118 of body tissue. As the leadingend portion 204 of the long thin member is expanded in the layer 118 ofbody tissue, the outer side surface of the resilient panel 240 appliesforce against the soft tissue of the layer 118 to move the tissuesufficiently to accommodate expansion of the leading end portion 204 ofthe long thin member 202.

When the tissue positioning assembly 200 is to be used in associationwith a fractured bone or bone fragments, the long thin member 202 ismoved through portions of the bone while the leading end portion 204 ofthe long thin member is in the contracted condition. Once the leadingend portion 204 of the long thin member 202 has moved through portionsof the bone separated by a fracture or break, the leading end portion ofthe long thin member may be expanded. The expanded leading end portion204 of the long thin member 202 would engage an outer surface of aportion of a bone in the same manner as in which the expanded leadingend portion engages an outer surface of the tissue layer 118 in FIGS.10-12.

A gripper member, corresponding to the gripper member 232 of FIG. 12, isthen moved axially along the long thin member 202 to press the portionof the bone disposed on one side of the fracture against a portion ofthe bone disposed on the opposite side of the fracture. In thisinstance, the leading end portion 204 of the long thin member 202 isexpanded at a location outside of the bone. However, in othersituations, it may be advantageous to expand the leading end portion 204of the long thin member 202 in the bone. The relatively soft cancellousbone can be deflected by expansion of the leading end portion 204 of thelong thin member 202 in a bone.

In the embodiment of the tissue positioning assembly 200 illustrated inFIGS. 16-19, the long thin member 202 has a leading end portion 204 withan external thread convolution 278. When the long thin member 202 isrotated about its longitudinal central axis, the external threadconvolution 278 engages body tissue. This enables force to betransmitted from the long thin member 202 to the body tissue engaged bythe external thread convolution 278. The body tissue 64 can then bemoved to and held in a desired position in a patient's body.

When the tissue positioning assembly 200 is to be utilized to positionthe layers 116 and 118 of the body tissue 64 relative to each other, thelong thin member 202 is extended through the upper (as viewed in FIG.16) layer 116 of body tissue. This may be done by forcing the long thinmember 202 to move axially through the layer 116 of body tissue with apiercing action. Alternatively, the long thin member 202 may be rotatedabout its longitudinal central axis. As the long thin member 202 isrotated, force is transmitted between the body tissue 116 and theexternal thread convolution 278. This force is effective to pull thelong thin member 202 through the body tissue 116. In order to minimizedamage to the body tissue 116, the long thin member 202 should rotateabout its longitudinal central axis so that the external threadconvolution 278 engages the body tissue 116 and is effective to pull thelong thin member 202 through the body tissue.

Once the long thin member 202 (FIG. 16) has moved through the upperlayer 116 of body tissue, the external thread convolution 278 on theleading end portion 204 of the long thin member 202 moves intoengagement with an upper side surface of the layer 118 of body tissue.When this happens, the long thin member 202 is again rotated about itslongitudinal central axis. This causes the external thread convolution278 to engage the lower layer 118 of body tissue with a screw action.The screw action between the thread convolution 278 and lower layer 118of body tissue is effective to pull the long thin member 202 into thelower layer 118 body tissue. When the external thread convolution 278has been screwed into the lower layer 118 of body tissue to a desireddepth, rotation of the long thin member 202 about its longitudinalcentral axis is interrupted.

In order to close a space 208 between the upper layer 116 and the lowerlayer 118 body tissue 64, the long thin member is pulled upward asindicated by the arrow 212 in FIG. 17. The upward force 212 applied tothe long thin member is transmitted through the external threadconvolution 278 to the lower layer 118 of body tissue. This pulls thelower layer 118 of body tissue upwards (as viewed in FIGS. 16 and 17)into engagement with the upper layer 116 of body tissue. If desired, thegripper member 232 (FIG. 12) may be used with the long thin member 202of FIGS. 17 and 18 to grip body tissue in the manner previouslyexplained.

Once the two layers 116 and 118 of body tissue have been moved to adesired position in the patient's body by the tissue positioningassembly 200, the anchor 60 (FIG. 18) may be moved into the body tissues116 and 118 by the robotic mechanism 38 in the same manner as previouslydiscussed in conjunction with FIGS. 2 and 3. Thus, the inserter member102 may be moved into engagement with the upper layer 116 of bodytissue. The pusher member 108 then applies force against the anchor 60to push the anchor through the lower layer 116 of body tissue and intothe lower layer 118 of body tissue. As was previously mentioned, theanchor 60 may be pushed through the lower layer 118 of body tissue orhave its movement into the lower layer interrupted when it is midwaybetween upper and lower side surfaces of the lower layer 118 of bodytissue.

While the anchor 60 is being pushed into the body tissue 116 and thebody tissue 118, an upwards force 212 is transmitted from the long thinmember 202 through the external thread convolution 278 to the lowerlayer 118 of body tissue. This force holds the lower layer of bodytissue in engagement with the upper layer 116 of body tissue in themanner illustrated schematically in FIG. 18.

It is contemplated that the long thin member 202 may be utilized as partof a fastener to interconnect the two layers 116 and 118 of body tissuein the manner illustrated schematically in FIG. 19. When this is to bedone, a retainer 72 is positioned along the long thin member 202 withthe long thin member extending through the retainer (FIG. 19). Theretainer pusher member 126 is then effective to press the retainer 72against the upper layer 116 of body tissue.

The retainer deformation assembly 144 can then be utilized to deform theretainer 72 in the manner previously discussed in conjunction with FIG.4. As force is applied against the retainer 72 by the force transmittingmembers 80 and 82, the retainer 72 is deformed and grips the long thinmember 202 to establish an interconnection between the retainer and thelong thin member. This interconnection results in force beingtransmitted through the long thin member 202 between the external threadconvolution 278 which engages the lower layer 118 of body tissue and theretainer 72 which engages the upper layer 116 of body tissue. After theretainer 72 has gripped the long thin member 202, the retainer pushermember 126 and retainer deformation assembly 144 are removed from thepatient's body. This results in the long thin member 202 and theretainer 72 functioning as a fastener to interconnect the two layers 116and 118 of body tissue.

The long thin member 202, the external thread convolution 278, and theretainer 72 may be formed of either biodegradable or non-biodegradablematerial. When the long thin member 202, external thread convolution 278and retainer 72 are formed of biodegradable material, they will degradeand be absorbed by the patient's body with passage of time. However,when the long thin member 202, external thread convolution, and retainer72 are formed of non-biodegradable material, they are effective tomaintain the two layers 116 and 118 of body tissue in engagement witheach other, in the manner illustrated in FIG. 19, for a long period oftime.

The long thin member 202 and external thread convolution 278 areillustrated in FIG. 19 in association with soft body tissue. However, itis contemplated that the long thin member 202 and external threadconvolution may be utilized in association with hard body tissue, suchas bone. When this is to be done, the external thread convolution 278 ofthe long thin member 202 may be screwed into the bone. Alternatively,the long thin member 202 and external thread convolution 278 may bemoved through a passage drilled in the bone and into a layer of softtissue. This would enable force to be transmitted from the externalthread convolution 278 to the layer of soft tissue to pull the layer ofsoft tissue into engagement with the bone.

It is believed that it may be particularly advantageous to utilize theexternal thread convolution 278 in association with the long thin member202 when pieces of bone are to be positioned relative to each other.Thus, the long thin member 202 may be moved through a passage drilled orformed in another manner, in one piece of bone and the external threadconvolution moved into engagement with a second piece of bone. The longthin member 202 would then be rotated about its central axis to screwthe external thread convolution 278 into the second piece of bone. Forceapplied to the long thin member 202 could then be utilized to pull thesecond piece of bone into engagement with the first piece of bone.

It is also contemplated that the long thin member 202 and externalthread convolution 278 may be advantageously utilized to close afracture or break in a bone. This is because the thread convolution 278may engage one portion of the bone to enable it to be pulled intoengagement with another portion of the bone. Once the two portions ofthe bone have been pulled into engagement with each other, they may beinterconnected in the manner disclosed in U.S. Pat. No. 6,117,160.Alternatively, they may be interconnected by securing a retainer 72 tothe long thin member 202 in the manner previously discussed herein.

Securing with Suture and Retainer

In the embodiments of the invention illustrated in FIGS. 2-8 the suture66 extends in a straight line between an anchor 60 and a retainer 72 orin a straight line between two retainers. However, under certaincircumstances at least, it may be desired to form the suture 66 into aloop which extends through body tissue 64 in the manner illustrated inFIG. 20.

The suture 66 is sewn through the two layers 116 and 118 of body tissueusing a needle or other known device. The suture is moved through thebody tissue 64 by the robotic mechanism 38. It is contemplated that themagnetic suturing system and method disclosed in the aforementioned U.S.patent application Ser. No. 10/005,652, will be used by the roboticmechanism 38. Alternatively, the needle could be manually moved throughthe two layers 116 and 118 of body tissue 64.

The suture 66 has a connector section 280 (FIG. 20) which extendsbetween a pair of a leg sections 282 and 284. The leg sections 282 and284 extend through the layers 116 and 118 of tissue 64 to the retainer72. The leg sections 282 and 284 extend through the retainer 72 and aretensioned by a tensioner 122 which applies a predetermined force 70 tothe two leg sections 282 and 284 of the suture 66.

While the suture 66 is being tensioned with the predetermined force 70,the retainer 72 is pressed against the body tissue 64 by the retainerpusher member 126. The retainer pusher member 126 is pressed against theretainer 72 by the pusher drive assembly 128. The pusher drive assembly128 causes the retainer pusher member 126 to press the retainer 72against the body tissue 64 with a predetermined force indicated at 74 inFIG. 16. This results in the retainer member 72 being pressed againstthe body tissue 64 with a predetermined force while the leg sections 282and 284 and connector section 280 of the suture 66 are tensioned with apredetermined force.

While the retainer 72 is pressed against the body tissue, the retainerdeformation assembly 144 deforms a retainer 72 to grip the two legsections 282 and 284 of the suture 66. Thus, the outer member 156 ismoved axially downward, as viewed in FIG. 20, to move the forcetransmitting members 80 and 82 radially inward toward the sphericalretainer 72. The force applied to the retainer 72 by the forcetransmitting members 80 and 82 deforms the retainer so that it grips thesutures 66. As was previously explained, the force transmitting members80 and 82 may be utilized to cause a cold flow of the material of theretainer 72 to grip the two legs 282 and 284 of the suture 66.Alternatively, ultrasonic vibratory energy from a source 90 may betransmitted to the force transmitting member 82 and the retainer 72 toheat the retainer.

Although the retainer has been illustrated in FIG. 16 as having aspherical configuration, it is contemplated that the retainer 72 couldhave a different configuration if desired. For example, the retainer 72could have any one of the configurations disclosed in U.S. Pat. No.6,159,234. The manner in which the retainer 72 is plastically deformedto grip the two legs 282 and 284 of the suture 66 may also be the sameas is disclosed in the aforementioned U.S. Pat. No. 6,159,234.Alternatively, the retainer 72 may be heated and then deformed in themanner disclosed in the aforementioned U.S. patent application Ser. No.09/524,397 or in U.S. Pat. No. 6,203,565.

In order to facilitate positioning of the suture 66 (FIG. 20) relativeto the body tissue 64, iron particles may be embedded in the suturethroughout the length of the suture. To move the suture 66 to a desiredposition in the patient's body, a magnet is positioned close enough tothe suture 66 to attract the iron particles in the suture. The magnet isthen moved relative to the body tissue to move the suture 66 relative tothe body tissue. The magnet may be positioned inside the patient's bodyor outside the patient's body. The magnet may be electromagnet or apermanent magnet.

Similarly, iron particles may be embedded in the suture retainer 72. Tomove the suture retainer 72 to a desired position in the patient's body,a magnet is positioned close enough to the retainer to attract the ironparticles in the retainer. The magnet is then moved relative to the bodytissue to move the suture retainer 72 relative to the body tissue. Themagnet may be positioned inside the patient's body or outside thepatient's body. The magnet may be an electromagnet or a permanentmagnet.

When iron particles are to be provided in the suture 66 and/or retainer72, the suture and/or retainer may advantageously be formed of abiodegradable material. As the biodegradable material of the suture 66and/or retainer 72 degrades in the patient's body, the iron particlesalso degrade. The iron particles are subsequently absorbed by thepatient's body.

Staple—Bonded

Leg Ends

In the embodiments of the invention illustrated in FIGS. 2-8, therobotic mechanism 38 is utilized to secure body tissue with a suture 66.However, it is contemplated that a staple 300 (FIGS. 21 and 22) may beutilized to secure the body tissue 64. When the staple 300 is utilizedto secure the body tissue, end portions 302 and 304 of legs 306 of thestaple are moved into engagement (FIG. 22) and bonded together. Bybonding the end portions 302 and 304 of the legs 306 and 308 of thestaple 300 together, the staple is locked into the tissue 64. Anytendency for the resilient legs 306 and 308 to spring back to theiroriginal positions (FIG. 21) is prevented by the interconnected the endportions 302 and 304 of the legs.

When the upper and lower layers 116 and 118 of the body tissue 64 are tobe interconnected, the long thin member 202 (FIGS. 9-12) is insertedthrough the layers 116 and 118 of body tissue. The leading end portion204 of the long thin member 202 is then expanded. The gripper member 232(FIG. 12) may then be moved along the long thin member 202 to clamp thelayers 116 and 118 of body tissue as illustrated in FIG. 12. It ispreferable to clamp the layers 116 and 118 of body tissue, but use ofthe gripper member may be eliminated. If desired, use of the entiretissue positioning assembly 200 could be eliminated.

Once the layers 116 and 118 of body tissue 64 have been gripped asillustrated schematically in FIG. 12, the two layers 116 and 118 of bodytissue are moved to a desired position in the patient's body and areheld there by the tissue positioning assembly 200. The robotic mechanism38 is then operated to move the staple 300 to a desired positionrelative to the body tissue 64 (FIG. 21). At this time, the legs 306 and308 of the staple 300 are in their initial or relaxed conditionillustrated in FIG. 21. The end portions 302 and 304 of the staple legsare spaced apart. This enables the staple 300 to be moved by the roboticmechanism 38 to a position in which body tissue 64 is disposed betweenthe end portions 302 and 304 of the staple legs 306 and 308 (FIG. 21).

Force transmitting members 312 and 314 (FIG. 21) are then moved by therobotic mechanism 38 to deflect the staple legs 306 and 308. The staplelegs 306 and 308 are deflected from their initial or unrestrainedpositioned illustrated in FIG. 21 to a bent or deflected position,illustrated in FIG. 22. As the staple legs 306 and 308 are bent underthe influence of force applied against the legs by the forcetransmitting members 312 and 314, the end portions 302 and 304 of thelegs move into engagement (FIG. 22) in the body tissue 64. Although theforce transmitting members 312 and 314 are moved by the roboticmechanism 38, it is contemplated that the force transmitting members 312and 314 could be moved manually if desired.

While the end portions 302 and 304 of the staple legs 306 and 308 arepressed together, ultrasonic vibratory energy is transmitted to thestaple 300 to effect the heating of the end portions 302 and 304 of thestaple legs 306 and 308 and a bonding of the staple legs together. Tothis end, ultrasonic vibratory energy is transmitted from the forcetransmitting member 312 to the staple legs 306 and 308. This results inthe force transmitting member 312 functioning as a horn for ultrasonicvibratory energy. The force transmitting member 314 functions as ananvil.

The apparatus for transmitting ultrasonic vibratory energy to the staplelegs 306 and 308 may have a construction and mode of operation which issimilar to the construction and mode of operation of the apparatusdisclosed in U.S. Pat. Nos. 5,836,897 and 5,906,625 and in U.S. patentapplication Ser. No. 09/524,397. However, it should be understood thatthe staple legs 306 and 308 could be heated with devices other thansources of ultrasonic vibratory energy. For example, a laser and/orresistance wire could be used to heat the staple legs 306 and 308.

The staple 300 is formed of a biodegradable polymeric material. However,staple 300 may be formed of any one of many different type of materials,including polymers of lactic acid, lactides, l-lactides, and isomers oflactic acids and/or lactides. Although it is believed that it may bedesired to form the staple 300 of polycaperlactone, other knownbiodegradable or non-biodegradable polymers may be utilized to form thestaple 300.

To effect a bonding of the end portions 302 and 304 of the staple legs306 and 308 together, the material of the end portions of the staplelegs is heated to a temperature in its transition temperature range bythe application of ultrasonic vibratory energy to the end portions 302and 304 of the staple legs 306 and 308. This results in the polymericmaterial of the end portions 302 and 304 of the staple legs 306 and 308changing from a rigid solid condition in which it has a fixed form to asoft or viscous condition. The material of the staple legs 306 and 308adjacent to the end portions 302 and 304 is not heated into itstransition temperature range and maintains its original configuration.

After the material the end portions 302 and 304 of the staple leg 306and 308 has been heated into the transition temperature range and has asoft moldable condition, the material moves under the influence of theforce applied against the staple legs 306 and 308 by the forcetransmitting members 312 and 314. The heated material of the staple legs306 and 308 molds itself together and blends at the end portions 302 and304 of the suture legs 306 and 308. The staple leg end portions 302 and304 are cooled to a temperature below the transition temperature rangeof the material of the staple 300 and a secure bond is obtained betweenthe polymeric material of the end portion 302 and the end portion 304 ofthe staple legs. This secure bond prevents a springing back of theresilient staple legs 306 and 308 toward their initial positions (FIG.21) relative to each other. Therefore, a portion of the body tissue 64is gripped between the end portions 302 and 304 of the staple legs 306and 308 and a connector or bight portion 318 of the staple 300 (FIG.22). The grip obtained by the staple 300 on the body tissue 64 holds thelayers 116 and 118 in secure engagement with each other.

Although only a single staple 300 has been illustrated in FIG. 21 alinear array of staples is provided along the ends of the side-by-sidelayers 116 and 118 of body tissue 64. This results in linear appositionof the layers 116 and 118 of body tissue 64. The two layers 116 and 118are interconnected in a side-by-side relationship by a plurality ofstaples in much the same manner as in which the layers 116 and 118 ofbody tissue are interconnected in FIG. 5.

One or more of the staples 300 and/or the anchors 60, sutures 66 andretainers 72 may be used for purposes other than the interconnecting oflayers 116 and 118 of body tissue. They may be used in association withthe repair of cartilage, pancreas, kidney, a stomach, a colon, etc. Theymay also be utilized in open or endoscopic surgery and may be applied bya robotic mechanism, similar to the robotic mechanism 38, or may bemanually applied. Additionally, they may be utilized for many differentpurposes, including rotator cuff repair, meniscus repair, the attachmentof soft tissue, such as a ligament or tendon to bone, interconnection ofvarious soft tissues to each other, and interconnections of portions ofbone, or with many different types of surgical implants, such as aprosthesis in a patient's body.

In the embodiment of FIGS. 21 and 22, the staple 300 forms a loop whichextends around a portion of the body tissue disposed between the endportions 302 and 304 of the staple legs 306 and 308 and the connector orbight portion 318 of the staple (FIG. 22). However, it is contemplatedthat the staple 300 may be embedded in body tissue at a location spacedfrom edge portions of the body tissue. For example, the staple may beutilized to connect a layer of body tissue or other material with arelatively large portion of body tissue which forms an organ or gland ormuscle in a patient's body, such as a pancreas or kidney. The staple 300(FIGS. 21 and 22) and/or suture connections of FIGS. 5, 6 and 8 may beutilized in association with components of a patient's bodycardiovascular system including the heart and/or blood vessels.

The tissue positioning assembly 200 of FIGS. 9-19 may be utilized toposition body tissue at any location where a staple 300 or sutureconnection of FIG. 5 is utilized. It should be understood that thecomponents of the tissue positioning assembly 200 will vary dependingupon the location where the staple or suture connection is to bepositioned. Thus, the tissue positioning assembly 200 may include onlythe long thin member 202. Alternatively, the tissue positioning assembly200 may include both the long thin member 202 and the gripper member 232(FIG. 12). The leading end portion 204 of the long thin member 202 maybe expanded at a location where expansion of the end portion 204deflects body tissue. Alternatively, the leading end portion 204 of thelong thin member 202 may be expanded at a location where the expansiondoes not deflect body tissue (FIG. 10). It is believed that the tissuepositioning assembly 200 will be particularly advantageous in holdingbody tissue during the application of a staple 300 or a sutureconnection. However, the tissue positioning assembly 200 may be usedduring many other surgical procedures on many different types of bodytissue.

Staple—Bonded

Leg Sides

The sides of legs of a staple 330 (FIGS. 23-26) are bonded together tohold the staple in the closed condition of FIG. 26. The staple 330 isformed of a polymeric material which may be either biodegradable ornonbiodegradable.

When the staple 330 (FIG. 23) is to be embedded into body tissue, therobotic mechanism 38 moves a staple mechanism 332 to a desired positionrelative to body tissue 334 (FIG. 24). The robotic mechanism 38 urgesthe staple mechanism toward the body tissue 334 with a predeterminedforce. When the staple mechanism 300 has been moved to the desiredposition relative to the body tissue 334, a pusher plate 338 is advancedor lowered from the position show in FIG. 23 through the position showin FIG. 24 to the position shown in FIG. 25. As the pusher plate 338 islowered or advanced to the position shown in FIG. 25, legs 342 and 344of the staple 330 are moved from a position spaced from the body tissue334 (FIG. 24) to a position in which the legs extend into the bodytissue (FIG. 25).

The staple 330 enters the body tissue 334, a connector or bight portion346 of the staple 330 moves into engagement with a pair of anvils 350and 352 (FIGS. 23-25). The anvils 350 and 352 are integrally formed withan anvil plate 354 (FIG. 23) disposed in the stapling mechanism 332. Atthis time, the legs 342 and 344 of the staple 330 extend into the bodytissue 334 (FIG. 25). However, the legs 342 and 344 extend in agenerally perpendicular relationship with the connector or bight portion346 of the staple 330 and do not engage each other. Although there issome gripping action between the legs 342 and 344 of the staple 330 andthe body tissue 334 at this time (FIG. 25), the staple 330 is notsecured in the body tissue.

Continued downward movement of the pusher plate 338 causes forcetransmitting members or lands 356 and 358 connected to the pusher plate338 to press against the connector or bight portion 346 of the staple330 (FIG. 25). As the pusher plate 338 continues to be advanced orlowered to the position shown in FIG. 26, the lands or forcetransmitting members 356 and 358 deflect or bend the legs 342 and 344 tothe gripping position illustrated in FIG. 26, to dispose a portion ofthe body tissue 334 between the legs 342 and 344 and the connector orbight portion 346 of the staple 330 (FIG. 26).

Longitudinally extending side surfaces of the staple legs 342 and 344are disposed in engagement with each other when the staple 330 is in thebent or deflected condition of FIG. 26. The longitudinally extendingside surfaces on the staple legs 342 and 344 engage at a location wherethe staple legs cross beneath (as viewed in FIG. 26) the connector orbight portion 346 of the staple.

Once the staple 330 has been bent or deformed to grip the body tissue334 in the manner illustrated schematically in FIG. 26, the legs 342 and344 of the staple are bonded together. The location where the endportions of the legs 342 and 344 cross and engage each other. To effecta bonding of the legs 342 and 344 to each other, the polymeric materialof the staple 330 is heated into its transition temperature range at thelocation where the end portions of the legs 342 and 344 of the staplelegs are disposed in engagement.

To effect a heating of the legs 342 and 344 of the staple, ultrasonicvibratory energy is transmitted from the land or force transmittingmember 356 to the staple 330. As this is done, the land or forcetransmitting member 356 functions as a horn for ultrasonic vibratoryenergy. The opposite land or force transmitting member 358 functions asan anvil of the ultrasonic vibratory energy application system. Theultrasonic vibratory energy application system may have a constructionsimilar to the construction disclosed in the aforementioned U.S. Pat.Nos. 5,836,897 and 5,906,625 or in U.S. patent application Ser. No.09/524,397. It should be understood that other known devices could beused to heat the staple 330. Thus, an electrical resistance wire heateror a laser could be used to heat the staple 330.

The staple 330 is formed of a polymeric material. The ultrasonicvibratory energy transmitted to the staple 330 from the forcetransmitting member 356 is effective to heat the polymeric material ofthe staple legs 342 and 344 into a transition temperature range for thematerial. When the material of the staple legs 342 and 344 is cooled, abond is formed between the staple legs in the same manner as previouslyexplained in conjunction with the staple 300 of FIGS. 21 and 22.

Once the legs 342 and 344 of the staple have been bonded together, thestaple is released or disengaged from the anvils 350 and 352 by aninjector spring 362 having legs 364 and 366 (FIG. 23) which are pressedagainst the staple 330. This force separates the staple from the anvils350 and 352.

It is contemplated that the staple mechanism 332 may have any one ofmany known constructions. It is also contemplated that the staple 330could have a configuration other than the configuration illustrated inFIGS. 23-26. For example, the staple 330 could have a constructionsomewhat similar to the construction of the staple 300 of FIG. 21.

The stapling mechanism 332 has a general construction and mode ofoperation which is similar is to the construction and mode of operationof a known stapling mechanism disclosed in U.S. Pat. No. 5,289,963.However, this known stapling mechanism does not bond the legs of astaple together. By bonding the legs 342 and 344 of the staple 330together, a resilient springing back of the legs toward their initialpositions and a resulting release of the body tissue 334 is prevented.

The staple 330 (FIGS. 23-26) is advantageously formed of a biodegradablepolymeric material, such as polycaperlatone. Staple 330 may also beformed of any one of many known biodegradable materials, includingpolymers or co-polymers of lactic acid, lactides, l-lactides, andisomers of lactic acids and/or lactides. Of course, the staple 330 maybe formed of many different known biodegradable materials. If desired,the staple 330 may be formed of a material which is not biodegradable.

The staple 330 will be utilized for tissue repair within a patient'sbody and in the locations on the surface of the patient's body.Regardless of whether the stapling mechanism 332 is used to stapleoutside of a patient's body or within the patient's body, the staplingmechanism may advantageously be utilized as part of the roboticmechanism 38 of FIG. 1. However, it should be understood that thestapling mechanism 332 could be manually actuated rather than berobotically actuated if desired.

The stapling mechanism 332 is illustrated in FIGS. 24-26 as connecting aflexible surgical mesh 380 with the body tissue 334. The roboticmechanism 38 may be used to position the surgical mesh 380 in thepatient's body. Movement of the surgical mesh 380 through the limitedincision 52 by the robotic mechanism 38 may be facilitated by moving themesh into the patient's body in a rolled up condition. The roboticmechanism 38 would then be operated to unroll the surgical mesh 380 inthe patient's body and position the surgical mesh relative to the bodytissue 334.

Although only a single staple 330 is illustrated in FIGS. 24-26, aplurality of staples 330 are utilized to connect the surgical mesh 380with the body tissue 334. In addition to staples 330, suture anchors 60,sutures 66 and retainers 72 (FIG. 5) may be utilized to connect thesurgical mesh 380 with the body tissue 334 in the manner previouslydescribed in conjunction with FIGS. 2-4. Both staples and sutureconnections may be utilized to connect the mesh 380 with the body tissue334. Alternatively, only staples or only suture connections may be usedto connect the surgical mesh 380 with the body tissue 334.

Implant of Viable Tissue Components

Rather than using the staple 330 to connect the surgical mesh 380 withthe body tissue 334, the staple 330 may be used to connect a scaffold orframework 382 (FIGS. 27-29) with the body tissue 334. The scaffold 382provides a non-living three dimensional matrix or supporting frameworkon which viable body tissue components 384 (FIGS. 27 and 28) aredisposed. The three dimensional framework or scaffold 382 may be formedof either biodegradable or a non-biodegradable material.

When the scaffold or framework 382 is formed of a non-biodegradablematerial, body tissue will grow through the scaffold or framework sothat the scaffold becomes embedded in new tissue growth. When thescaffold or framework 382 is formed of a biodegradable material, thescaffold will eventually degrade and be absorbed by body tissue. Thescaffold 382 may have fibers of biodegradable material randomly arrangedin the manner illustrated schematically in FIG. 27 to form a supportingframework. Alternatively, the scaffold or framework 382 may havebiodegradable fibers arranged in an ordered relationship similar to therelationship illustrated schematically in FIG. 28.

It is contemplated that the scaffold or framework 382 may have either aflexible or rigid construction. The scaffold 382 could be formed of abiodegradable material such as polyglycolic acid or polylactic acid. Ifdesired, the scaffold or framework 382 could be formed of fibrousconnective materials such as portions of body tissue obtained from humanand/or animal sources. The scaffold or framework 382 may be formed ofcollagen or submucosal tissue.

The scaffold or matrix 382 forms a supporting framework for tissueinductive factors and viable tissue components 384. The viable tissuecomponents 384 may be mesenchymal cells which are introduced into thescaffold or framework in the operating room. Thus, the matrix orscaffold 382 may be constructed at a location remote from an operatingroom. After the scaffold 382 has been transported to the operating room,the viable tissue components 384, such as mesenchymal cells, may beintroduced into the scaffold.

It is contemplated that the matrix or scaffold 382 may contain viabletissue components 384 which include stem cells and/or fetal cells. Thestem cells and/or fetal cells may be introduced into the matrix orscaffold 382 in the operating room. It is contemplated that tissuegrowth inductive factors may be provided in the matrix or scaffold 382along with any desired type of precursor cells. The scaffold or matrix382 may also contain viable tissue components 384 which are viableplatelets centrifuged from blood in a manner similar to that describedin U.S. patent application Ser. No. 09/483,676, filed Jan. 14, 2000 andU.S. Pat. No. 6,174,313. The viable tissue components 384 may befragments harvested from a patient in the manner disclosed in theaforementioned U.S. Pat. No. 6,174,313.

The scaffold or matrix 382 may have a layered construction with each ofthe layers being formed at different materials. Each of the layers ofthe scaffold or matrix may be impregnated with a different materialand/or contain different viable tissue components 384. For example,precursor cells may be provided in one layer of the scaffold or matrix382 and tissue growth inductive factors and/or antibotics may beprovided in another layer of the scaffold or matrix. The scaffold ormatrix 382 may be formed of body tissue such as allograft or autograft.The viable tissue components 384 in the scaffold or matrix 382 may beobtained from the patient or from another human being. Alternatively,the viable tissue components 384 may be obtained from an animal.

The scaffold 382 and viable tissue components 384 may be utilized tocreate organ or gland structure or tissue, such as structural tissue ofa pancreas, liver, or kidney. The scaffold or matrix 382 and viabletissue components 384 may be used in the repair of components of apatient's cardiovascular system including the heart and/or bloodvessels. It should be understood that a plurality of different types ofviable cells may be provided on a single three dimensional matrix orscaffold 382.

The scaffold 382 and viable tissue components 384 may advantageously bepositioned in the patient's body by the robotic mechanism 38. When thescaffold 382 and viable tissue components 384 are to be positioned inthe patient's body by the robotic mechanism 38, the scaffold and viabletissue components are moved through the limited incision 52 (FIG. 1) bythe robotic mechanism 38. When the scaffold or matrix 382 has a rigidstructure, the scaffold may be formed as a plurality of separatesections. The rigid sections of the scaffold 382 are sequentially movedthrough the limited incision 52 and secured to tissue in the patient'sbody with suitable fasteners, such as the staple 330 and/or suture 66,anchor 60 and retainer 72 fasteners of FIG. 5, by the robotic mechanism38. The sections of the scaffold 382 may be secured in any desiredmanner, including the manner illustrated in FIGS. 2-4 or FIGS. 23-26herein.

When the scaffold or matrix 382 (FIGS. 27-29) has a flexible structure,the scaffold may be rolled up outside the patient's body to form acylinder. The rolled up scaffold 382, with the viable tissue components384 thereon, is moved through the limited incision 52 (FIG. 1) into thepatient's body by operation of the robotic mechanism 38. Once the rolledup scaffold 382 and viable tissue components 384 (FIGS. 27-29) have beenmoved into the patient's body by the robotic mechanism 38, the roboticmechanism unrolls the flexible scaffold 382 with the viable tissuecomponents 384 on the scaffold. The robotic mechanism 38 is thenoperated to position the unrolled scaffold 382 and viable tissuecomponents 384 relative to tissue in the patient's body. The unrolledscaffold 382 is connected with the patient's body tissue with suitablefasteners, such as the staples 330 and/or suture, anchor and retainerfasteners of FIG. 5, by the robotic mechanism 38. The scaffold 382 maybe secured in any desired manner, including the manner illustrated inFIGS. 2-4 or FIGS. 23-26 herein. While the robotic mechanism 38 mayposition and secure the scaffold 382 with the viable tissue components384 on the scaffold, this may also be done manually.

The tissue positioning assembly 200 (FIG. 30) may be used to positionthe scaffold 382 and viable tissue components 384 relative to the bodytissue 334. When this is to be done, the long thin member 202 is movedthrough the scaffold 382 into the body tissue 334 with the leading endportion 204 of the long thin member in the contracted condition of FIG.9. The leading end portion 204 is then expanded in the body tissue 334(FIG. 30). Alternatively, the leading end portion 204 may be movedthrough the body tissue and then expanded, in the manner illustrated inFIGS. 10, 11, and 12.

A gripper member 232 (FIG. 30) may be moved along the long thin member202. The gripper member 232 is pressed against the scaffold 382, in themanner indicated by the arrow 234. This results in the scaffold 382being pressed against the body tissue 334. The scaffold 382 and aportion of the body tissue 334 are clamped between the gripper member232 and expanded end portion 204 of the long thin member 202.

The long thin member 202 (FIG. 30) and gripper member 232 are used togrip the scaffold 382 and body tissue 334 and to move them to anydesired position in the patient's body. In addition, the gripper member232 and long thin member 202 hold the scaffold 382 and body tissue 334in a desired relationship to each other and to other tissue in thepatient's body during securing of the scaffold to the body tissue withthe staple 330 and/or other fasteners. If desired, a retainer 72 may besecured to the long thin member, in the manner illustrated in FIG. 19.This would enable the long thin member 202 (FIG. 30) to be used as aportion of a fastener interconnecting the scaffold 382 and body tissue334.

The viable tissue components 384 may be positioned in the patient's bodyin ways other than using the scaffold or matrix 382. Thus, body tissuecomponents, including viable body tissue components 384, may beharvested from a human or animal body in the manner disclosed in theaforementioned U.S. Pat. No. 6,174,313. The tissue components may thenbe shaped to form a body having a desired configuration. The tissuecomponents may be shaped using a press in the manner disclosed in U.S.Pat. No. 6,132,472. Alternatively, the tissue components may be shapedto a desired configuration by a molding process. The molding process maybe performed using a press similar to any one of the presses disclosedin U.S. Pat. No. 6,132,472. Alternatively, the molding process may beperformed using an open mold. The resulting shaped body of tissuecomponents, including viable tissue components, may be secured in apatient's body using the robotic mechanism 38 and one or more of thefasteners disclosed herein.

Tissue Retractors

The robotic mechanism 38 (FIG. 1) may be used to position a tissueretractor assembly 392 (FIG. 31) relative to body tissue. The roboticmechanism effects operation of the tissue retractor assembly 392 from acontracted condition to an expanded condition to move body tissue. Thismovement of body tissue may advantageously create a space for theperformance of a surgical procedure by the robotic mechanism 38. Thus,space could be created for the positioning of a suture connection of thetype illustrated in FIG. 5 and/or for a staple connection of the typeillustrated in FIGS. 22 and 26. Of course, other surgical procedurescould be conducted in the space created by expansion of the tissueretractor assembly 392.

The tissue retractor assembly 392 (FIG. 31) includes a tubular,cylindrical cannula or scope 396. A tubular, cylindrical shaft 398 isdisposed in a coaxial relationship with the cannula or scope 396 andextends axially through the cannula or scope. However, if desired, theshaft 398 may be offset to one side of the cannula or scope 396. Thiswould facilitate the insertion of one or more surgical instrumentsthrough the cannula 396 to a working space 400 created by expansion of aballoon or bladder 402 from the contracted condition shown in dash linesin FIG. 31 to the expanded condition in solid lines in FIG. 31.

As the bladder or balloon expands, portions of body tissue 406 aredeflected under the influence of force applied to the body tissue by thebladder or balloon 402. If desired, the bladder or balloon 402 may havea toroidal configuration with a central passage so that surgicalinstruments may be inserted through the balloon to a working space 404offset to the right (as viewed in FIG. 31) of the balloon. Expansion ofthe balloon 402 may be utilized to conduct a surgical procedure, such asdissection.

The tubular shaft 398 has a central passage through which fluid, such asa liquid or gas, may be conducted to the bladder or balloon 402 toeffect expansion of the bladder or balloon from the contracted conditionto the expanded condition. The shaft 398 and cannula or scope 396 areconnected with the robotic mechanism 38 (FIG. 1) to enable the roboticmechanism to position the tissue retractor assembly 392 relative to thebody tissue 406 and to enable the robotic mechanism to control the flowof fluid to the bladder or balloon 402 to thereby control the extent ofexpansion of the bladder or balloon.

It is contemplated that the tissue retractor assembly 392 may have aconstruction which is different than the construction illustrated inFIG. 26. Thus, the tissue retractor assembly 392 may have any one of theconstructions disclosed in U.S. Pat. Nos. 6,042,596 and 6,277,136. Therobotic mechanism may be utilized to effect operation of a selectedtissue retractor assembly in the same manner as is disclosed in theaforementioned U.S. Pat. Nos. 6,042,596 and 6,277,136.

If the tissue retractor assembly is to effect separation of body tissuesalong naturally occurring planes, the robotic mechanism 38 may beoperated to move the tissue retractor assembly 392 to the desiredposition in a patient's body where the balloon or bladder 402 is filledwith fluid to effect expansion of the bladder or balloon to thecondition illustrated in solid lines in FIG. 26. The bladder or balloonis then contracted, by exhausting fluid from the bladder or balloon 402through the shaft 398. The robotic mechanism 38 may be then operated toadvance either just the contracted bladder or balloon 402 relative tothe body tissue 406 or to advance the entire tissue retractor assembly392 relative to the body tissue. Once the bladder or balloon 402 hasbeen advanced, with or without the cannula scope 396, by operation ofthe robotic mechanism 38, the bladder or balloon 402 is again expanded.This sequential contraction, advancement, and expansion of the bladderor balloon may be repeated any desire number of times to effect thedesired separation of portions of the body tissue 406.

It is contemplated that the balloon or bladder 402 may be left in apatient's body. When this is to be done, the balloon or bladder 402 maybe formed of a biodegradable material. Of course, components of theretractor assembly 392 other than the balloon bladder 402 may be formedof biodegradable material.

A tissue retractor assembly may be utilized to separate bones at ajoint. In FIG. 32, a tissue retractor assembly 410 is positioned in ashoulder joint 412. Specifically, the robotic mechanism 38 is operatedto position the tissue retractor assembly 410 relative to a humeral head414, achromium 416 and rotator cuff 418 in the shoulder joint 412.

Once the tissue retractor assembly 410 has been positioned at a desiredlocation in the shoulder joint 412, the robotic mechanism 38 effectsexpansion of a balloon or bladder in the tissue retractor assembly 410from a contracted condition to an expanded condition. This effectsmovement of the achromium 416 relative to the rotator cuff 418. Thisincreases the space in the shoulder joint for the surgeon to work on thebody tissue. The manner in which the tissue retractor assembly 410 isused in the shoulder joint 412 is similar to the manner disclosed in theaforementioned in U.S. Pat. No. 6,277,136.

In FIG. 32, the tissue retractor assembly 410 is utilized to createspace within a shoulder joint 412. However, it is contemplated that therobotic mechanism 38 may be utilized to position a contracted tissueretractor assembly relative to other joints in a patient's body and toeffect expansion of the tissue retractor assembly to create space inthese joints. For example, the tissue retractor assembly may be utilizedin association with a knee joint in a leg of a patient or with vertebraein a patient's spinal column.

When a tissue retractor assembly is to be utilized to create space in ajoint in a patient's spinal column, the contracted tissue retractorassembly may be inserted between adjacent vertebrae. A balloon orbladder in the tissue retractor assembly is then expanded under theinfluence of fluid pressure to increase the space between the vertebrae.Depending upon the construction of the tissue retractor assembly and theposition where it is located in the patient's spinal column by therobotic mechanism 38, the expansion of the tissue retractor assembly canseparate adjacent vertebrae without significantly changing the spacialorientation of vertebrae relative to each other. Alternatively, thetissue retractor assembly may be positioned by the robotic mechanism 38at a location where expansion of the tissue retractor assembly resultsin a tilting or pivoting movement of one vertebra relative to anadjacent vertebra. The tissue retractor assembly may have any one of theconstructions disclosed in the aforementioned U.S. Pat. Nos. 6,042,596and 6,277,136.

A tissue retractor assembly 422 (FIG. 33) is moved through an openingformed in a vertebrae 424 in a patient's spinal column. The roboticmechanism 38 may be utilized to form the opening in the vertebrae 424and to move the contracted tissue retractor assembly 422 into thevertebra.

Once the robotic mechanism 38 has been operated to position the tissueretractor assembly relative to the vertebra 424, the robotic mechanismeffects expansion of a bladder or balloon 426 from a contractedcondition to the expanded condition illustrated schematically in FIG.33. As this occurs, marrow is compressed within the vertebra 424. Thetissue retractor assembly 422 includes a cannula or scope 428 which isutilized to position the balloon or bladder 426 relative to the vertebra424 and to conduct the fluid (gas or liquid) into the balloon or bladder426 to effect expansion of the balloon or bladder. The balloon orbladder 426 may be formed of a biodegradable material.

The tissue retractor assembly 422 is subsequently contracted from theexpanded condition of FIG. 33 and withdrawn from the vertebra 424. Whenthis has been done, flowable synthetic bone material or cement may beconducted through a cannula into the space in the vertebra 424. It iscontemplated that the robotic mechanism 38 will be utilized to positionthe cannula through which the flow of synthetic bone material or cementis conducted into the space created in the vertebra 424 by expansion ofthe balloon or bladder 426. The manner in which the balloon or bladder426 may compress the marrow within the vertebra 424 and create a spacewhich is subsequently filled with synthetic bone material or cement isthe same as is disclosed in U.S. Pat. No. 4,969,888.

The balloon or bladder 426 may be formed of a biodegradable material andfilled with bone growth inductive factors. The bone growth inductivefactors may include bone particles and bone morphogenetic protein.Viable tissue components may be provided in the balloon or bladder 426.The balloon or bladder 426 will degrade with the passage of time andenable bone or other tissue to grow in the space created in the vertebra424. The balloon or bladder 426 may be filled with a patient's bodytissue components harvested in the manner disclosed in U.S. Pat. No.6,174,313.

In FIG. 33, the tissue retractor assembly 422 has been illustrated inconjunction with a vertebra in a patient's body. It is contemplated thatthe tissue retractor assembly could be utilized in association withother bones in a patient's body. By utilizing the robotic mechanism 422to position the tissue retractor assemblies 392, 410 and 422 (FIGS.31-33) relative to a patient's body, the tissue retractor assemblies canbe accurately positioned. The robotic mechanism 38 controls the fluidpressure and thus the force conducted to the bladder or balloon in thetissue retractor assemblies 392, 410 and 422. In addition, the use ofthe robotic mechanism 38 to control the operation of the tissueretractor assemblies 392, 410 and 422 enables the size of an incisionthrough which the tissue retractor assemblies are inserted to beminimized and the size of an incision for surgical instruments toperform the surgical procedure in space created by operation of thetissue retractor assemblies is minimized.

Threaded Fasteners

The robotic mechanism 38 may also be utilized to secure body tissue witha threaded fastener 440 as illustrated in FIG. 34. Of course, therobotic mechanism 38 may be used with other fasteners if desired. Forexample, the robotic mechanism 38 could be used in association withfasteners having any one of the constructions disclosed in U.S. Pat.Nos. 5,293,881; 5,720,753; 6,039,753; and 6,203,565.

The robotic mechanism 38 includes a programmable computer 444 (FIG. 34)which is connected with a fastener drive member 446 by a motor 448. Inaddition to the motor 448, a force measurement assembly 450 is connectedwith fastener drive member 446 and computer 444. The force measurementassembly 450 has an output to the computer 444 indicating the magnitudeof resistance encountered by the fastener drive member 446 to rotationof the fastener 440. A position sensor 452 is connected with fastenerdrive member 446 and the computer 444. The position sensor 452 has anoutput which is indicative of the position of the fastener drive member446. The output from the position sensor 452 indicates the depth ordistance to which the threaded fastener is moved into body tissue byoperation of the motor 448 to rotate the fastener drive member 446.

The threaded fastener 440 includes a head end portion 456 with a recess458 which receives a polygonal projection 460 from the fastener drivemember 446. Rotation of the fastener drive member 446 by the motor 448causes the projection 460 to transmit drive torque to the head endportion 456 of the fastener 440.

As the fastener 440 is rotated, a thread convolution 462 on a shankportion 464 engages body tissue. The thread convolution 462 has a spiralconfiguration. The thread convolution cooperates with the body tissue topull the threaded fastener into the body tissue as the threaded fasteneris rotated.

By utilizing the robotic mechanism 38 to manipulate the fastener 440,the fastener can be accurately positioned relative to body tissue. Theoutput from the force measurement assembly 450 to a computer 444 enablesthe force, that is resistance to rotation on the threaded fastener 440,to be controlled during rotation of the fastener. This prevents theapplication of excessive force to the body tissue. In addition, theposition sensor 452 enables the distance to which the fastener 440 ismoved into the body tissue to be accurately controlled.

Implant

In addition to fasteners to secure tissue in a patient's body, therobotic mechanism 38 may be utilized to position prosthetic implants ina patient's body. During joint replacement surgery and other surgicalprocedures, prosthetic implants may be placed in a patient's body. Therobotic mechanism 38 may be utilized to control movement of a cuttingtool during resection of bone in a patient's body.

It is contemplated that the joint replacement surgery may include kneejoint replacement. The computer 38 may be utilized to effect a cuttingof end portions of a tibia and/or femur in the manner disclosed in U.S.patent application Ser. No. 09/976,396 filed Oct. 11, 2001, by Peter M.Bonutti and entitled Method of Performing Surgery. In addition, therobotic mechanism 38 may be utilized to position a prosthetic implant,such as a tibial tray 470 (FIG. 35) relative to a proximal end portion472 of a tibia 474 in a leg 476 of a patient. The tibial tray 470 has akeel 478 which is inserted into the proximal end portion 472 of thetibia 474 in the leg 476 of the patient during a knee replacementoperation.

During the knee replacement operation, the robotic mechanism 38 effectsa resection of both the tibia 474 and femur 480 in the leg 476 of thepatient. The robotic mechanism 38 then moves a force transmitting member484 to move the keel 478 of the tibial tray 470 through a limitedincision 488 in the leg 476 of the patient.

The robotic mechanism 38 includes a programmable computer 444 which isconnected with the force transmitting member 484 by a motor 492.Operation of the motor 492 is effective to move the force transmittingmember and tibial tray 470 relative to the tibia 472 to force the keel478 of the tibial tray 470 into the tibia 472. A force measurementassembly 494 is connected with the force transmitting member 484 and thecomputer 444. The output from the force measurement assembly 494 isindicative of a resistance encountered by the force transmitting member484 in moving the tibial tray 470 into the tibia 474. By monitoring theoutput from the force measurement assembly 494, the computer 444 canprovide an indication to a surgeon of the resistance being encounteredto movement of the keel 478 of the tibial tray into the tibia 474 in thepatient's leg 476.

A position sensor 496 is connected with the force transmitting member484 and the computer 444. The position sensor 496 has an outputindicative of the position of the force transmitting member 484 relativeto the proximal end portion 472 of the tibia 474. This enables a surgeonto monitor the extent movement of the keel 478 on the tibial tray intothe proximal end portion 472 of the tibia 474.

The motor 492 has an operating mechanism which effects a pounding of thetibial tray 470 into the proximal end portion 472 of the tibia 474 inmuch the same manner as in which a hammer has previously been utilizedto pound the tibial tray 470 into the 474. However, it is believed thatit may be desired to effect the operation of the motor 492 to move theforce transmitting member 484 and tibial tray 470 with a continuousinsertion stroke without pounding on the tibial tray. This would resultin the tibial tray 470 being slowly pressed into the proximal endportion 472 of the tibia 474 with a continuous movement which ismonitored by the output from the force measurement assembly 494 and theposition sensor 496. By moving the tibial tray 470 with a smoothinsertion stroke, accurate insertion of the tibial tray into the tibia474 is facilitated.

Once the robotic mechanism 38 has been utilized to position the tibialtray 470, a related component of a replacement knee joint may bepositioned on the femur 480 by the robotic mechanism. The roboticmechanism 38 may also be utilized to check stability of the knee jointin flexion, extension, and/or rotation. In the manner in which therobotic mechanism is utilized to perform these functions is the same asdisclosed in the aforementioned U.S. patent application Ser. No.09/976,396.

Imaging

It is contemplated that various imaging arrangements may be utilized toenable a surgeon to monitor a surgical procedure, while using therobotic mechanism 38. In the embodiment illustrated in FIG. 1, thesingle imaging device 40 is utilized to enable imaging of a locationwhere a surgical procedure is being conducted by the robotic mechanism38 to be transmitted to a monitor 48. Stereoscopic and videostereoscopic viewing of the location where a surgical procedure is beingperformed by the robotic mechanism 38 may also be desired.

A pair of endoscopes 502 and 504 (FIG. 36) may be used in associationwith the robotic mechanism 38. The endoscopes 502 and 504 are disposedin predetermined angular orientations relative to each other. The outputfrom the endoscopes 502 and 504 is conducted to the computer 44.

The viewing screen of the monitor 48 may be divided into two sectionswith one section being a monoscopic, that is, two dimensional, imageresulting from the output of the endoscope 502. The other section of thescreen of the monitor 48 has a monoscopic, that is, two dimensional,image resulting from the output of the endoscope 504. The monitor 508may be utilized to provide a steroscopic image, that is, a threedimensional image, resulting from the output of both of the endoscopes502 and 504. The manner in which the stereoscopic images may be obtainedfrom the two endoscopes 502 and 504 at the monitor 508 is similar tothat disclosed in U.S. Pat. Nos. 4,651,201 and 5,474,519.

By providing a three dimensional image at the monitor 508, a surgeon hasa realistic view of the area where the robotic mechanism 38 isperforming a surgical procedure. This enables the surgeon to conductstereotactic surgery.

A navigation system may also provide inputs to the computer 44 to assistin the control of the robotic mechanism 38 and the performance of thesurgical procedure. The navigation system may include transmittersconnected with the robotic mechanism 38. Transmitters may also beconnected with the endoscope 502 and 504.

If desired, a plurality of navigation members may be connected withtissue in the patient's body by the robotic mechanism 38. Reflective endportions of the navigation members are disposed in the patient's bodyand are illuminated by light conducted along fiber optic pathways in theendoscopes 502 and 504. Images of the ends of the navigation members areconducted from the endoscopes 502 and 504 to the monitors 48 and 508.The images of the ends of the navigation members enable a surgeon todetermine the relative positions of body tissue in the patient's bodyduring performance of a surgical procedure with the robotic mechanism.

Alternatively, the navigation members may extend through the patient'sskin into engagement with one or more tissues in a patient's body.Reflective ends of the navigation members would be disposed outside ofthe patient's body and would be visible to the surgeon. In addition, thereflective ends of the navigation members would be visible to an opticalsensing system connected with the computer 44 and robotic mechanism 38.Relative movement between the reflective ends of the navigation memberswould be sensed by the optical sensing system and would enable thecomputer 44 to determine the relative positions of tissues in thepatient's body. In addition, relative movement between the reflectiveends of the navigation members could be visually sensed by the surgeonand would enable the surgeon to determine the relative positions oftissues in the patient's body based on direct observation of thenavigation members.

For example, the navigation members could be connected with one or morebones in a patient's body. When the reflective ends of the navigationmembers are disposed in the patient's body, the endoscope 502 and 504can be used to determine the location of one or more bones relative toother tissues. When the reflective ends of the navigation members aredisposed outside the patient's body, the surgeon and/or an opticalsensing system can determine the location of one or more bones relativeto other tissues.

Rather than using two endoscopes 502 and 504 to obtain images, anultrasonic imaging device may be used with only one of the endoscopes.For example, the endoscope 504 could be omitted or merely turned off. Aknown ultrasonic imaging device may be used to provide images which aretransmitted to the computer 44. The ultrasonic imaging device may beconstructed and operated in a manner similar to that disclosed in U.S.Pat. Nos. 5,897,495 and 6,059,727. The images which are transmitted tothe computer 44 from the ultrasonic imaging device may be used to createmonoscopic images at the monitor 48. Alternatively, the images from theultrasonic imaging device may be combined with images from the endoscope502 to create stereoscopic images. If desired, the stereoscopic imagesmay be created in the manner disclosed in U.S. Pat. No. 6,059,727.

The images provided by the endoscopes 502 and 504 and/or an ultrasonicimaging device enable the surgeon to monitor the performance of any ofthe surgical procedures disclosed herein. Additionally, variouscombinations of the foregoing steps may be included in the surgicalprocedures. For all surgical procedures, the images provided at themonitors 48 and 508 (FIG. 36) by the endoscopes 502 and 504 and/or theultrasonic imaging device will facilitate performance of the surgicalprocedure in the patient's body with the robotic mechanism 38.

The robotic mechanism 38 may be utilized with a fluoroscope 520 (FIG.37). The general construction and mode of operation of the fluoroscope520 and an associated control unit 522 is the same as is disclosed inU.S. Pat. Nos. 5,099,859; 5,772,594; 6,118,845 and/or 6,198,794. Theoutput from an endoscope 524 is transmitted to a computer 526. An imageresulting from operation of the fluoroscope 520 is transmitted from thecontrol unit 522 to the computer 526. This enables a monitor for thecomputer 526 to provide either two separate monoscopic, that is twodimensional, and/or a single stereoscopic or three dimensional viewcorresponding to the output from both the fluoroscope 520 and theendoscope 524. This may be done by having the computer 526 connectedwith two monitors, corresponding to the monitors 48 and 508 of FIG. 36.

The three dimensional image provided by the monitor connected with thecomputer 526 results from a combining of images obtained with theendoscope 524 and fluoroscope 520. The three dimensional image enables asurgeon to have a clear view of a location in a patient's body where therobotic mechanism 38 is being utilized to perform a surgical procedure.Of course, the surgical procedure performed by the robotic mechanism 38may involve the securing of body tissue and/or a scaffold containingviable tissue components with fasteners in the manner previouslyexplained herein. Alternatively, the surgical procedure may involve themoving and/or dissecting of body tissue with one of the retractors ofFIGS. 31-33. The cooperation between the fluoroscope 520 and endoscope524 facilitates the performance of stereotactic surgical proceduresutilizing the robotic mechanism 38.

If desired, an ultrasonic imaging device may be used with either or bothof the fluoroscope 520 and endoscope 524. Images obtained with theultrasonic imaging device may be used with images from the fluoroscopeand/or endoscope to provide wither stereoscopic or monoscopic images atmonitors which are visible to the surgeon and correspond to the monitors48 and 508 of FIG. 36.

A magnetic resonance imaging unit 530 (FIG. 38) may be utilized inassociation with the robotic mechanism 38 during performance of asurgical procedure on the patient 34. The magnetic resonance imagingunit 530 (MRI) provides an image of a location where the surgicalprocedure is being performed in a patient's body. The portion of therobotic mechanism 38 exposed to a magnetic field generated during use ofthe magnetic resonance imaging unit 530 (MRI) is formed of non-magneticmaterials. Thus, the portion of the robotic mechanism 38 which extendsinto the magnetic field of the magnetic resonance imaging unit 530 isformed of a material which does not respond to a magnetic field. Thesematerials may include polymeric materials and metals which are notresponsive to a magnetic field.

An endoscope 534 (FIG. 38) cooperates with the magnetic resonanceimaging unit 530 (MRI) to provide for imaging of the location in thepatient 34 where a surgical procedure is being conducted by the roboticmechanism 38. Nonmagnetic materials, primarily polymeric materials, maybe used in the endoscope 534. A monitor 538 is disposed at a locationwhere it is visible to the surgeon and is outside of a magnetic fieldresulting from operation of the magnetic resonance imaging unit 530. Themonitor 538 is connected with a computer (not shown) which is connectedwith both the endoscope 534 and the magnetic resonance imaging unit 530.

The monitor 538 may provide the surgeon a stereoscopic image, that is, athree dimensional image, resulting from outputs of the magneticresonance imaging unit 530 and the endoscope 534. Alternatively, theimaging unit 538 may provide one monoscopic image, that is, a twodimensional image corresponding to the output of the magnetic resonanceimaging unit 530 and a second monoscopic image corresponding to theoutput of the endoscope 534. The endoscope 534 is constructed ofnon-magnetic materials which are not effected by the magnetic field ofthe magnetic resonance imaging unit 530.

Rather than using a magnetic resonance imaging unit 530 to provide animage in association with the endoscope 534, the image may be providedby computerized tomographic scanning and/or positron emissiontomography. Regardless of which of the imaging devices is utilized toprovide an image of the area where surgical procedure is beingconducted, it is believed that it would be advantageous to utilize therobotic mechanism 38 to conduct the surgical procedure.

Markers

In order to facilitate a surgeon's visualization of the location ofarticles utilized during the performance of surgical procedures by therobotic mechanism 38, markers may be provided in association with thearticles. The markers which are utilized in association with one or morearticles should be readily detected in an image provided by an imagingunit associated with the robotic mechanism 38. When the endoscopes 40,502, 504, 524 and/or 534 are associated with the robotic mechanism 38,the markers should be clearly visible in an image transmitted to amonitor, such as the monitor 48, 508, and/or 538 from one or more of theendoscopes. When the fluoroscope 520 (FIG. 27) is associated with therobotic mechanism 38, the markers should be clearly visible in imagestransmitted to a monitor from the fluoroscope and/or an associatedendoscope. Similarly, when a magnetic resonance imaging unit 530 (FIG.38) is associated with the robotic mechanism 38, the markers should beclearly visible in an image transmitted to the monitor 538 from themagnetic resonance imaging unit.

To facilitate locating articles with the endoscopes 40, 502, 504, 524,and/or 534, light reflective particles may be used as markers. The lightreflective particles are illuminated by light conducted along fiberoptic pathways in the endoscopes. The light reflective particles may beembedded in the material of the anchor 60 and the suture retainer 72.Alternatively, a light reflective coating could be provided on theexterior of the anchor 60 and/or suture retainer 72. It is alsocontemplated that light reflective particles could be included in thematerial of the suture 66.

The staples 300 and 330 (FIGS. 21-26) may be provided with markers tofacilitate locating the staples in an image from the endoscopes 40, 502,504, 524 and/or 534. The markers may be reflective particles embedded inthe material of the staple 300 or 330. Alternatively, a reflectivecoating could be provided on the staple 300 or 330. The reflectiveparticles may be embedded in only the connector or bight portions 318and 346 of the staples 300 and 330. Similarly, the coating of reflectivematerial may be applied to only the connector or bight portions 318 and346 of the staples 300 and 330.

In order to facilitate positioning of the scaffold 382 and viable tissuecomponents 384, light reflective particles may be connected withportions of the scaffold 382. Thus, a marker formed of light reflectiveparticle may be provided at each of the corners of the rectangularscaffold 382 illustrated in FIG. 29. Of course, if the scaffold 382 hada different configuration, light reflective particles would be providedat different locations on the scaffold. Regardless of the configurationof the scaffold 382, it is preferable to locate the light reflectiveparticles adjacent to the periphery of the scaffold.

The light reflective particles may be disposed in small groups at spacedlocations on the scaffold. Alternatively, the light reflective particlesmay be disposed in one or more threads which extend along one or moreedges of the scaffold. The light reflective particles are formed of asubstance which is compatible with the patient's body and reflectslight. For example, polished titanium, gold, or platinum particles couldbe utilized. Alternatively, crystals which reflect light may be used asmarkers. The crystals may be formed of a salt and dissolve in apatient's body.

When the markers are to be used with the fluoroscope 520 and endoscope524, it is believed that it may be preferred to form the marker of aradiopaque material which is also reflective. For example, polishedparticles of titanium, would reflect light so as to be visible in animage transmitted from the endoscope 524 and would be radiopaque so asto be visible in an image transmitted from the fluoroscope 520. It iscontemplated that the radiopaque and light reflective particles could beformed off of other materials if desired. For example, a particle whichis radiopaque and another particle which is reflective may be utilized.The radiopaque particle would be visible in the image transmitted fromthe fluoroscope 520 and the reflective particle would be visible in animage transmitted from the endoscope 534.

The reflective radiopaque particles may be embedded in the material ofthe anchor 60 and suture retainer 72. In addition, the particles may beembedded in the material of the suture 66. Alternatively, the radiopaqueand light reflective particles may be provided as a coating on at leasta portion of the anchor 60, suture retainer 72 and/or suture 66.

When the robotic mechanism 38 of FIG. 37 is to be utilized inassociation with the fluoroscope 520 and endoscope 524 to position thescaffold 382, a light reflective and radiopaque marker may be connectedwith the scaffold. The light reflective and radiopaque marker may beformed by polished particles of titanium disposed at selected locationsalong the periphery of the scaffold 382. Alternatively, the marker couldbe formed of a combination of light reflective particles and radiopaqueparticles. The light reflective particles would be visible in imagestransmitted by the endoscope 524 and the radiopaque particles would bevisible in images transmitted by the fluoroscope 520.

The magnetic resonance imaging unit 530 has a relatively strong magneticfield. Therefore, markers provided in association with articles to beused during performance of a surgical procedure to be imaged with themagnetic resonance imaging unit 530 cannot be formed of a magnetic ormagnetizable material. Images transmitted to the monitor 538 from themagnetic resonance imaging unit 530 (FIG. 38) are readily visible ifthey have a relatively high water or hydrogen content. Therefore,capsules of Vitamin E may be associated with articles to be used duringthe performance of surgery by the robotic mechanism 38 and imaging withthe magnetic residence imaging unit 530. These capsules may be connectedwith the article or may be embedded in the article. When the capsulesare to be embedded in the article, it is believed that it may bepreferred to utilize relatively small microcapsules which will notsignificantly impair the strength of the materials in which they areembedded. The microcapsules may contain Vitamin E, water, or air.

The microcapsules may be embedded in the material of the anchor 60and/or suture retainer 72. The microcapsules may also be embedded in thematerial of the staples 300 and 330. This would enable the anchor 60,suture retainer 72 and/or staples 300 and 330 to be readily visible inan image transmitted from the magnetic resonance imaging unit 530.

When articles are to be imaged with the magnetic resonance imaging unit530, the articles may be marked by a coating of hydrophilic material.The coating of hydrophilic material absorbs body liquid and increasesthe contrast between the articles and the surrounding environment. Forexample, the staple 300 (FIGS. 21 and 22) and/or the staple 330 (FIGS.23-26) may be coated with hydrophilic material. The areas of the stapleswhich are to be bonded together, that is, the end portions 302 and 304of the staple 300 and the side surfaces of the legs 342 and 344 of thestaple 330 (FIGS. 24 and 26), may be left free of the hydrophilicmaterial to promote a formation of a bond between the legs of thestaple. They hydrophilic material may be a jell formed of materials suchas algin, vegetable gums, pectins, starches, and/or of complex proteinssuch as gelatin and collagen.

The scaffold 382 may have one or more fibers formed of a hydrophilicmaterial. Alternatively, small bodies of hydrophilic material could bepositioned at various locations along the periphery of the scaffold 382.It is contemplated that the entire scaffold 382 could be formed ahydrophilic material, such as collagen.

A marker which is to be used with an endoscope 40, 502, 504, 524, and/or534 may be a luminescent material. The luminescent material may be inthe form of crystals such as zinc or cadmium sulfide. Alternatively, theluminescent material may be a dye. The marker may havechemiluminescence, bioluminescence, photoluminescence ortriboluminescence.

The luminescent material forming a marker may be disposed on the surfaceof the anchor 60, suture retainer 72, and/or the suture 66. It iscontemplated that the luminescent material forming a marker may form acoating over a portion of either the staple 300 (FIGS. 21 and 22) or thestaple 330 (FIGS. 23-26).

It is contemplated the markers for use with the endoscopes 40, 502, 504,524 and/or 534 may be used with fasteners other than the particularfasteners enclosed herein. Thus, one or more of the various markerspreviously described herein may be utilized in connection with a bondedrivet of the type disclosed in U.S. Pat. No. 6,203,565. Of course, themakers may be used in association with any of the other surgicalimplants disclosed in the aforementioned U.S. Pat. No. 6,203,565.

The markers previously described herein may be utilized with any one ofthe expandable retractor assemblies 392, 410, or 422 (FIGS. 31-33) toindicate the positions of the retractor assemblies in an image on amonitor visible to a surgeon. The markers may be positioned on theballoons or bladders in the retractor assemblies 392, 410 and 422. Thus,a marker may be provided on the balloon or bladder 402 in the retractorassembly 392.

The marker on the balloon or bladder 402 (FIG. 31) may be lightreflective so as to be detectable in an image provided by an endoscope40 (FIG. 1). The marker on the balloon or bladder 402 may also beradiopaque so as to be detectable in an image provided by a fluoroscope520 (FIG. 37). It is contemplated that a layer or coating of hydrophilicmaterial could be provided on the balloon or bladder 402 to facilitatedetection of the balloon or bladder in an image provided by the magneticresonance imaging unit 530 (FIG. 38).

CONCLUSION

In view of the foregoing description, it is clear that the presentinvention relates to a method of securing either hard or soft bodytissue. A robotic mechanism 38 or manual effort may be used to positiona fastener relative to the body tissue. The fastener may be a suture 66,staple 300 or 330, screw 440, or other known device.

The fastener may be a suture 66 which is tensioned with a predeterminedforce by a robotic mechanism 38 or manual effort. The robotic mechanism38 or manual effort may also be used to urge a retainer 72 toward bodytissue 64 with a predetermined force. The suture 66 may be gripped withthe retainer 72 while the suture is tensioned with a predetermined forceand while the retainer is urged toward the body tissue 64 with apredetermined force.

Alternatively, the fastener may be a staple 300 or 330. A roboticmechanism 38 or manual effort may be utilized to position the staplerelative to body tissue. The robotic mechanism 38 or manual effort mayeffect a bending of the staple 300 or 330 to move legs of the stapleinto engagement with each other. The legs of the staple 300 or 330 maybe bonded together at a location where the legs of the staple aredisposed in engagement.

Regardless of what type of fastener is utilized, a positioning apparatus200 may be used to position the body tissue 64 before and/or duringsecuring with a fastener. The positioning apparatus may include a longthin member 202 which transmits force to the body tissue. Force may betransmitted from an expanded end portion 204 of the long thin member 202to the body tissue 64. A second member 232 may cooperate with the longthin member 202 to grip the body tissue. The long thin member 202 may bepositioned relative to the body tissue by a robotic mechanism 38 ormanual effort.

Various imaging devices may be utilized to assist in positioning afastener, such as a rivet suture or staple, relative to body tissue.Under certain circumstances at least, it may be desirable to utilize twoor more different types of imaging devices. Thus, an endoscope 534 and amagnetic resonance imaging apparatus (MRI) 530 may be utilized toprovide an image. Alternatively, an endoscope 524 and a fluoroscopicdevice 520 may be utilized. If desired, ultrasonic imaging devices maybe utilized in association with another imaging device, such as anendoscope or magnetic resonance imaging device. One or more markers maybe provided on fasteners to facilitate location of the fasteners in animage.

A fastener (FIG. 5, 22, or 26) may be utilized to secure a scaffold 382containing viable tissue components 384 in place on body tissue 334. Thetissue components 384 may be stem cells, fetal cells, mesenchymal cells,and/or any desired type of precursor cells. It is contemplated that thescaffold 382 with one or more different types of tissue components maybe positioned at any desired location within a patient's body, such aswithin an organ, by the robotic mechanism 38. For example, the scaffold382 could be positioned in the pancreas or liver of a patient.Alternatively, the scaffold 382 could be connected with a bone in thepatient's body. The scaffold 382 may be positioned relative to the bodytissue by the robotic mechanism 38 or manual effort. One or more markersmay be provided on the scaffold to facilitate location of the scaffoldin an image.

It is contemplated that the robotic mechanism 38 may advantageously beutilized to position surgical implants other than fasteners in apatient's body. For example, the robotic mechanism 38 may be utilized toposition a prosthesis 470 in a patient's body. If desired, the roboticmechanism 38 may be utilized to position a screw type fastener 440 at aspecific location in a patient's body. The robotic mechanism 38 may beused to position a scaffold 382 containing viable tissue componentsrelative to body tissue.

What is claimed is:
 1. A method of using a robotic guidance system forperforming surgery on a spine, the method comprising: utilizing at leastone computerized tomographic scan image of a location on a spinal columnof a patient on whom a surgical procedure is to be performed, whereinthe at least one computerized tomographic scan image is connected to atleast one computer and visible on at least one monitor connected to theat least one computer; attaching at least one coupling component to thespinal column of the patient; coupling at least one marker to the atleast one coupling component; imaging, with a fluoroscope, at least oneview of the spinal column of the patient on whom the surgical procedureis to be performed, wherein the at least one fluoroscope image istransmitted to the at least one computer and visible on the at least onemonitor connected to the at least one computer, and wherein the at leastone marker is clearly visible in the at least one fluoroscope image;positioning a cannula, with a robotic mechanism, to a first positionrelative to a vertebra in the spinal column of the patient; drilling apassage through the cannula into bone of the vertebra in the spinalcolumn of the patient; inserting a guidewire through the cannula intothe passage in the bone of the vertebra in the spinal column of thepatient; and positioning a screw into the bone of the vertebra in thespinal column of the patient, wherein the screw is configured to securebody tissue.
 2. The method according to claim 1, wherein at least one ofdrilling a passage further comprises drilling a passage, with a manualeffort, through the cannula positioned with the robotic mechanism intobone of the vertebra in the spinal column of the patient, inserting aguidewire further comprises inserting a guidewire, with a manual effort,through the cannula positioned with the robotic mechanism into thepassage in the bone of the vertebra in the spinal column of the patient,and positioning a screw further comprises positioning a screw, with amanual effort, into the bone of the vertebra in the spinal column of thepatient, wherein the screw is configured to secure body tissue.
 3. Themethod according to claim 1, further comprising: positioning thecannula, with the robotic mechanism, to a second position different fromthe first position relative to the vertebra in the spinal column of thepatient; drilling a second passage through the cannula positioned in thesecond position into bone of the vertebra in the spinal column of thepatient; inserting a second guidewire through the cannula positioned inthe second position into the second passage in the bone of the vertebrain the spinal column of the patient; and positioning a second screw, inthe second position, into the bone of the vertebra in the spinal columnof the patient, wherein the second screw is configured to secure bodytissue.
 4. The method according to claim 3, wherein at least one ofdrilling a second passage further comprises drilling a second passage,with a manual effort, through the cannula positioned in the secondposition with the robotic mechanism into bone of the vertebra in thespinal column of the patient, inserting a second guidewire furthercomprises inserting a guidewire, with a manual effort, through thecannula positioned in the second position with the robotic mechanisminto the second passage in the bone of the vertebra in the spinal columnof the patient, and positioning a second screw further comprisespositioning a screw, with a manual effort, positioned in the secondposition, into the bone of the vertebra in the spinal column of thepatient, wherein the second screw is configured to secure body tissue.5. The method according to claim 1, further comprising: positioning thecannula, with the robotic mechanism, to a second position different fromthe first position relative to at least one of a second position on thesame vertebra in the spinal column of the patient, an adjacent vertebrain the spinal column of the patient, and a different vertebral structurein the spinal column of the patient; drilling a second passage throughthe cannula positioned in the second position into at least one of boneof the same vertebra, bone of the adjacent vertebra, and the differentvertebral structure in the spinal column of the patient; inserting asecond guidewire through the cannula positioned in the second positioninto the second passage in at least one of the bone of the samevertebra, the bone of the adjacent vertebra, and the different vertebralstructure in the spinal column of the patient; and positioning a secondscrew, positioned in the second position, into at least one of the boneof the same vertebra, the bone of the adjacent vertebra, and thedifferent vertebral structure, wherein the second screw is configured tosecure body tissue.
 6. The method according to claim 5, furthercomprising: drilling a second passage further comprises drilling asecond passage, with a manual effort, through the cannula positioned inthe second position with the robotic mechanism into at least one of thebone of the same vertebra, the bone of the adjacent vertebra, and thedifferent vertebral structure in the spinal column of the patient;inserting a second guidewire further comprises inserting a guidewire,with a manual effort, through the cannula positioned in the secondposition with the robotic mechanism into the second passage into atleast one of the bone of the same vertebra, the bone of the adjacentvertebra, and the different vertebral structure in the spinal column ofthe patient; and positioning a second screw further comprisespositioning a screw, with a manual effort, through the cannulapositioned in the second position with the robotic mechanism into atleast one of the bone of the same vertebra, the bone of the adjacentvertebra, and the different vertebral structure in the spinal column ofthe patient, wherein the second screw is configured to secure bodytissue.
 7. The method according to claim 1, wherein the cannula is atleast one portion of a tissue retractor assembly.
 8. The methodaccording to claim 1, further comprising positioning at least one tissueretractor through the cannula positioned by the robotic mechanism. 9.The method according to claim 1, further comprising utilizing at leastone surgical instrument positioned through the cannula.
 10. The methodaccording to claim 1, wherein the guidewire is configured to haveexternal threads.
 11. The method according to claim 10, wherein theguidewire is configured to be screwed into the passage in the bone. 12.The method according to claim 1, wherein the body tissue is at least aportion of one of a bone, ligament, tendon, and muscle.
 13. A method ofusing a robotic guidance system for performing surgery on a spine, themethod comprising: utilizing at least one computerized tomographic scanimage of a location on a spinal column of a patient on whom a surgicalprocedure is to be performed, wherein the at least one computerizedtomographic scan image is connected to at least one computer and visibleon at least one monitor connected to the at least one computer;attaching at least one coupling component to the spinal column of thepatient; coupling at least one marker to the at least one couplingcomponent; imaging, with a fluoroscope, at least one view of the spinalcolumn of the patient on whom the surgical procedure is to be performed,wherein the at least one fluoroscope image is transmitted to the atleast one computer and visible on the at least one monitor connected tothe at least one computer, and wherein the at least one marker isclearly visible in the at least one fluoroscope image; positioning acannula, with a robotic mechanism, to a first position relative to thespinal column of the patient; and inserting a surgical instrumentthrough the cannula, wherein the surgical instrument is configured foruse in the surgical procedure on the spinal column of the patient. 14.The method according to claim 13, wherein inserting a surgicalinstrument further comprises inserting a surgical instrument, with amanual effort, through the cannula positioned with the roboticmechanism, wherein the surgical instrument is configured for use in thesurgical procedure on the spinal column of the patient.
 15. The methodaccording to claim 13, further comprising: positioning the cannula, withthe robotic mechanism, to a second position different from the firstposition relative to the spinal column of the patient; and inserting asurgical instrument through the cannula positioned in the secondposition, wherein the surgical instrument is configured for use in thesurgical procedure on the spinal column of the patient.
 16. The methodaccording to claim 15, wherein inserting a surgical instrument furthercomprises inserting a surgical instrument, with a manual effort, throughthe cannula positioned in the second position with the roboticmechanism, wherein the surgical instrument is configured for use in thesurgical procedure on the spinal column of the patient.
 17. The methodaccording to claim 13, wherein the cannula is at least one portion of atissue retractor assembly.
 18. The method according to claim 13, furthercomprising positioning at least one tissue retractor through thecannula.
 19. The method according to claim 13, further comprisingpositioning at least one prosthetic implant in the spinal column of thepatient.
 20. A robotic guidance system for performing surgery on aspine, the robotic guidance system comprising: at least one computerconfigured to receive at least one computerized tomographic scan imageof a spinal column of a patient on whom a surgical procedure is to beperformed; at least one monitor connected to the at least one computer,wherein the at least one monitor is configured to display, from the atleast one computer, the at least one computerized tomographic scan imageof the spinal column of the patient on whom the surgical procedure is tobe performed; at least one coupling component configured to couple tothe spinal column of the patient; at least one marker configured tocouple to the at least one coupling component, wherein the at least onemarker is configured to be clearly visible in at least one fluoroscopeimage of the spinal column of the patient on whom the surgical procedureis to be performed, and wherein at least one fluoroscope image istransmitted to the at least one computer and visible on the at least onemonitor connected to the at least one computer; a robotic mechanismconnected to the at least one computer and configured to move throughvarious programmed motions for the performance of the surgical procedureon the spinal column of the patient; a cannula configured to bepositioned, by the robotic mechanism, relative to at least one vertebraein the spinal column of the patient; a drill configured to create atleast one passage into bone of the at least one vertebrae in the spinalcolumn of the patient, wherein the drill is configured to be positionedthrough the cannula; at least one guidewire configured to be insertedinto the at least one passage in the bone of the at least one vertebraein the spinal column of the patient, wherein the guidewire ispositionable through the cannula; and at least one screw configured tobe positioned into the at least one passage in the bone of the at leastone vertebrae in the spinal column of the patient, wherein the at leastone screw is configured to secure body tissue.
 21. The robotic guidancesystem according to claim 20, wherein the cannula is at least oneportion of a tissue retractor assembly.
 22. The robotic guidance systemaccording to claim 20, further comprising at least one tissue retractorconfigured to be positioned through the cannula.
 23. The roboticguidance system according to claim 20, further comprising at least onesurgical instrument configured to be utilized through the cannula. 24.The robotic guidance system according to claim 20, wherein the guidewireis configured to have external threads.
 25. The robotic guidance systemaccording to claim 24, wherein the guidewire is configured to be screwedinto the passage in the bone.
 26. The robotic guidance system accordingto claim 20, wherein the body tissue is at least a portion of one of abone, ligament, tendon, and muscle.
 27. The robotic guidance systemaccording to claim 20, further comprising at least one prostheticimplant configured to be positioned in the bone of the at least onevertebrae in the spinal column of the patient.
 28. A robotic guidancesystem for performing surgery on a spine, the robotic guidance systemcomprising: at least one computer configured to receive at least onecomputerized tomographic scan image of a spinal column of a patient onwhom a surgical procedure is to be performed; at least one monitorconnected to the at least one computer, wherein the at least one monitoris configured to display, from the at least one computer, the at leastone computerized tomographic scan image of the spinal column of thepatient on whom the surgical procedure is to be performed; at least onecoupling component configured to couple to the spinal column of thepatient; at least one marker configured to couple to the at least onecoupling component, wherein the at least one marker is configured to beclearly visible in at least one fluoroscope image of the spinal columnof the patient on whom the surgical procedure is to be performed, andwherein at least one fluoroscope image is transmitted to the at leastone computer and visible on the at least one monitor connected to the atleast one computer; a robotic mechanism connected to the at least onecomputer and configured to move through various programmed motions forthe performance of the surgical procedure on the spinal column of thepatient; a cannula configured to be positioned, by the roboticmechanism, relative to the spinal column of the patient; and at leastone surgical instrument configured for use in the surgical procedure onthe spinal column of the patient, wherein the surgical instrument ispositionable through the cannula.
 29. The robotic guidance systemaccording to claim 28, wherein the cannula is at least one portion of atissue retractor assembly.
 30. The robotic guidance system according toclaim 28, further comprising at least one tissue retractor configured tobe positioned through the cannula.
 31. The robotic guidance systemaccording to claim 28, further comprising at least one prostheticimplant configured to be positioned in the spinal column of the patient.